GI and Hepatology News

Emerging research indicates that phenotype-based testing may help identify which biologic process is driving an individual’s obesity, enabling clinicians to better tailor antiobesity medication (AOM) to the patient.

Currently, patient response to AOMs varies widely, with some patients responding robustly to AOMs and others responding weakly or not at all.

For example, trials of the GLP-1 semaglutide found that 32%-39.6% of people are “super responders,” achieving weight loss in excess of 20%, and a subgroup of 10.2%-16.7% of individuals are nonresponders. Similar variability was found with other AOMs, including the GLP-1 liraglutide and tirzepatide, a dual GLP-1/glucose-dependent insulinotropic polypeptide receptor agonist.

Studies of semaglutide suggest that people with obesity and type 2 diabetes (T2D) lose less weight on the drug than those without T2D, and men tend to lose less weight than women.

However, little else is known about predictors of response rates for various AOMs, and medication selection is typically based on patient or physician preference, comorbidities, medication interactions, and insurance coverage.

Although definitions of a “nonresponder” vary, the Endocrine Society’s latest guideline, which many clinicians follow, states that an AOM is considered effective if patients lose more than 5% of their body weight within 3 months.

Can nonresponders and lower responders be identified and helped? Yes, but it’s complicated.

“Treating obesity effectively means recognizing that not all patients respond the same way to the same treatment, and that’s not a failure; it’s a signal,” said Andres Acosta, MD, PhD, an obesity expert at Mayo Clinic, Rochester, Minnesota, and a cofounder of Phenomix Sciences, a biotech company in Menlo Park, California.

“Obesity is not a single disease. It’s a complex, multifactorial condition driven by diverse biological pathways,” he told GI & Hepatology News. “Semaglutide and other GLP-1s primarily act by reducing appetite and slowing gastric emptying, but not all patients have obesity that is primarily driven by appetite dysregulation.”

 

Phenotype-Based Profiling

Figuring out what drives an individual’s obesity is where a phenotype-based profiling test could possibly help.

Acosta and colleagues previously used a variety of validated studies and questionnaires to identify four phenotypes that represent distinct biologic drivers of obesity: hungry brain (abnormal satiation), emotional hunger (hedonic eating), hungry gut (abnormal satiety), and slow burn (decreased metabolic rate). In their pragmatic clinical trial, phenotype-guided AOM selection was associated with 1.75-fold greater weight loss after 12 months than the standard approach to drug selection, with mean weight loss of 15.9% and 9%, respectively.

“If a patient’s obesity isn’t primarily rooted in the mechanisms targeted by a particular drug, their response will naturally be limited,” Acosta said. “It’s not that they’re failing the medication; the medication simply isn’t the right match for their biology.”

For their new study, published online in Cell Metabolism, Acosta and colleagues built on their previous research by analyzing the genetic and nongenetic factors that influenced calories needed to reach satiation (Calories to Satiation [CTS]) in adults with obesity. They then used machine learning techniques to develop a CTS gene risk score (CTS-GRS) that could be measured by a DNA saliva test.

The study included 717 adults with obesity (mean age, 41; 75% women) with marked variability in satiation, ranging from 140 to 2166 kcals to reach satiation.

CTS was assessed through an ad libitum meal, combined with physiological and behavioral evaluations, including calorimetry, imaging, blood sampling, and gastric emptying tests. The largest contributors to CTS variability were sex and genetic factors, while other anthropometric measurements played lesser roles.

Various analyses and assessments of participants’ CTS-GRS scores showed that individuals with a high CTS-GRS, or hungry brain phenotype, experienced significantly greater weight loss when treated with phentermine/topiramate than those with a low CTS-GRS, or hungry gut, phenotype. After 52 weeks of treatment, individuals with the hungry brain phenotype lost an average of 17.4% of their body weight compared with 11.2% in those with the hungry gut phenotype.

An analysis of a separate 16-week study showed that patients with the hungry gut phenotype responded better to the GLP-1 liraglutide, losing 6.4% total body weight, compared to 3.3% for those with the hungry brain phenotype.

Overall, the CTS-GRS test predicted drug response with up to 84% accuracy (area under the curve, 0.76 in men and 0.84 in women). The authors acknowledged that these results need to be replicated prospectively and in more diverse populations to validate the test’s predictive ability.

“This kind of phenotype-based profiling allows us to predict which patients are more likely to respond and who might need a different intervention,” Acosta said. “It’s a critical step toward eliminating trial-and-error in obesity treatment.”

The test (MyPhenome test) is used at more than 80 healthcare clinics in the United States, according to Phenomix Sciences, which manufactures it. A company spokesperson said the test does not require FDA approval because it is used to predict obesity phenotypes to help inform treatment, but not to identify specific medications or other interventions. “If it were to do the latter,” the spokesperson said, “it would be considered a ‘companion diagnostic’ and subject to the FDA clearance process.”

 

What to Do if an AOM Isn’t Working?

It’s one thing to predict whether an individual might do better on one drug vs another, but what should clinicians do meanwhile to optimize weight loss for their patients who may be struggling on a particular drug?

“Efforts to predict the response to GLP-1 therapy have been a hot topic,” noted Sriram Machineni, MD, associate professor at Montefiore Medical Center, Bronx, New York, and founding director of the Fleischer Institute Medical Weight Center at Montefiore Einstein. Although the current study showed that genetic testing could predict responders, like Acosta, he agreed that the results need to be replicated in a prospective manner.

“In the absence of a validated tool for predicting response to specific medications, we use a prioritization process for trialing medications,” Machineni told GI & Hepatology News. “The prioritization is based on the suitability of the side-effect profile to the specific patient, including contraindications; benefits independent of weight loss, such as cardiovascular protection for semaglutide; average efficacy; and financial accessibility for patients.”

Predicting responders isn’t straightforward, said Robert Kushner, MD, professor of medicine and medical education at the Feinberg School of Medicine at Northwestern University and medical director of the Wellness Institute at Northwestern Memorial Hospital in Chicago.

“Despite looking at baseline demographic data such as race, ethnicity, age, weight, and BMI, we are unable to predict who will lose more or less weight,” he told GI & Hepatology News. The one exception is that women generally lose more weight than men. “However, even among females, we cannot discern which females will lose more weight than other females,” he said.

If an individual is not showing sufficient weight loss on a particular medication, “we first explore potential reasons that can be addressed, such as the patient is not taking the medication or is skipping doses,” Kushner said. If need be, they discuss changing to a different drug to improve compliance. He also stresses the importance of making lifestyle changes in diet and physical activity for patients taking AOMs.

Often patients who do not lose at least 5% of their weight within 3 months are not likely to respond well to that medication even if they remain on it. “So, early response rates determine longer-term success,” Kushner said.

Acosta said that if a patient isn’t responding to one class of medication, he pivots to a treatment better aligned with their phenotype. “That could mean switching from a GLP-1 to a medication like [naltrexone/bupropion] or trying a new method altogether,” he said. “The key is that the treatment decision is rooted in the patient’s biology, not just a reaction to short-term results. We also emphasize the importance of long-term follow-up and support.”

The goal isn’t just weight loss but also improved health and quality of life, Acosta said. “Whether through medication, surgery, or behavior change, what matters most is tailoring the care plan to each individual’s unique biology and needs.”

The new study received support from the Mayo Clinic Clinical Research Trials Unit, Vivus Inc., and Phenomix Sciences. Acosta is supported by a National Institutes of Health grant.

Acosta is a co-founder and inventor of intellectual property licensed to Phenomix Sciences Inc.; has served as a consultant for Rhythm Pharmaceuticals, Gila Therapeutics, Amgen, General Mills, Boehringer Ingelheim, Currax Pharmaceuticals, Nestlé, Bausch Health, and Rare Diseases; and has received research support or had contracts with Vivus Inc., Satiogen Pharmaceuticals, Boehringer Ingelheim, and Rhythm Pharmaceuticals. Machineni has been involved in semaglutide and tirzepatide clinical trials and has been a consultant to Novo Nordisk, Eli Lilly and Company, and Rhythm Pharmaceuticals. Kushner is on the scientific advisory board for Novo Nordisk.

A version of this article appeared on Medscape.com.

Emerging research indicates that phenotype-based testing may help identify which biologic process is driving an individual’s obesity, enabling clinicians to better tailor antiobesity medication (AOM) to the patient.

Currently, patient response to AOMs varies widely, with some patients responding robustly to AOMs and others responding weakly or not at all.

For example, trials of the GLP-1 semaglutide found that 32%-39.6% of people are “super responders,” achieving weight loss in excess of 20%, and a subgroup of 10.2%-16.7% of individuals are nonresponders. Similar variability was found with other AOMs, including the GLP-1 liraglutide and tirzepatide, a dual GLP-1/glucose-dependent insulinotropic polypeptide receptor agonist.

Studies of semaglutide suggest that people with obesity and type 2 diabetes (T2D) lose less weight on the drug than those without T2D, and men tend to lose less weight than women.

However, little else is known about predictors of response rates for various AOMs, and medication selection is typically based on patient or physician preference, comorbidities, medication interactions, and insurance coverage.

Although definitions of a “nonresponder” vary, the Endocrine Society’s latest guideline, which many clinicians follow, states that an AOM is considered effective if patients lose more than 5% of their body weight within 3 months.

Can nonresponders and lower responders be identified and helped? Yes, but it’s complicated.

“Treating obesity effectively means recognizing that not all patients respond the same way to the same treatment, and that’s not a failure; it’s a signal,” said Andres Acosta, MD, PhD, an obesity expert at Mayo Clinic, Rochester, Minnesota, and a cofounder of Phenomix Sciences, a biotech company in Menlo Park, California.

“Obesity is not a single disease. It’s a complex, multifactorial condition driven by diverse biological pathways,” he told GI & Hepatology News. “Semaglutide and other GLP-1s primarily act by reducing appetite and slowing gastric emptying, but not all patients have obesity that is primarily driven by appetite dysregulation.”

 

Phenotype-Based Profiling

Figuring out what drives an individual’s obesity is where a phenotype-based profiling test could possibly help.

Acosta and colleagues previously used a variety of validated studies and questionnaires to identify four phenotypes that represent distinct biologic drivers of obesity: hungry brain (abnormal satiation), emotional hunger (hedonic eating), hungry gut (abnormal satiety), and slow burn (decreased metabolic rate). In their pragmatic clinical trial, phenotype-guided AOM selection was associated with 1.75-fold greater weight loss after 12 months than the standard approach to drug selection, with mean weight loss of 15.9% and 9%, respectively.

“If a patient’s obesity isn’t primarily rooted in the mechanisms targeted by a particular drug, their response will naturally be limited,” Acosta said. “It’s not that they’re failing the medication; the medication simply isn’t the right match for their biology.”

For their new study, published online in Cell Metabolism, Acosta and colleagues built on their previous research by analyzing the genetic and nongenetic factors that influenced calories needed to reach satiation (Calories to Satiation [CTS]) in adults with obesity. They then used machine learning techniques to develop a CTS gene risk score (CTS-GRS) that could be measured by a DNA saliva test.

The study included 717 adults with obesity (mean age, 41; 75% women) with marked variability in satiation, ranging from 140 to 2166 kcals to reach satiation.

CTS was assessed through an ad libitum meal, combined with physiological and behavioral evaluations, including calorimetry, imaging, blood sampling, and gastric emptying tests. The largest contributors to CTS variability were sex and genetic factors, while other anthropometric measurements played lesser roles.

Various analyses and assessments of participants’ CTS-GRS scores showed that individuals with a high CTS-GRS, or hungry brain phenotype, experienced significantly greater weight loss when treated with phentermine/topiramate than those with a low CTS-GRS, or hungry gut, phenotype. After 52 weeks of treatment, individuals with the hungry brain phenotype lost an average of 17.4% of their body weight compared with 11.2% in those with the hungry gut phenotype.

An analysis of a separate 16-week study showed that patients with the hungry gut phenotype responded better to the GLP-1 liraglutide, losing 6.4% total body weight, compared to 3.3% for those with the hungry brain phenotype.

Overall, the CTS-GRS test predicted drug response with up to 84% accuracy (area under the curve, 0.76 in men and 0.84 in women). The authors acknowledged that these results need to be replicated prospectively and in more diverse populations to validate the test’s predictive ability.

“This kind of phenotype-based profiling allows us to predict which patients are more likely to respond and who might need a different intervention,” Acosta said. “It’s a critical step toward eliminating trial-and-error in obesity treatment.”

The test (MyPhenome test) is used at more than 80 healthcare clinics in the United States, according to Phenomix Sciences, which manufactures it. A company spokesperson said the test does not require FDA approval because it is used to predict obesity phenotypes to help inform treatment, but not to identify specific medications or other interventions. “If it were to do the latter,” the spokesperson said, “it would be considered a ‘companion diagnostic’ and subject to the FDA clearance process.”

 

What to Do if an AOM Isn’t Working?

It’s one thing to predict whether an individual might do better on one drug vs another, but what should clinicians do meanwhile to optimize weight loss for their patients who may be struggling on a particular drug?

“Efforts to predict the response to GLP-1 therapy have been a hot topic,” noted Sriram Machineni, MD, associate professor at Montefiore Medical Center, Bronx, New York, and founding director of the Fleischer Institute Medical Weight Center at Montefiore Einstein. Although the current study showed that genetic testing could predict responders, like Acosta, he agreed that the results need to be replicated in a prospective manner.

“In the absence of a validated tool for predicting response to specific medications, we use a prioritization process for trialing medications,” Machineni told GI & Hepatology News. “The prioritization is based on the suitability of the side-effect profile to the specific patient, including contraindications; benefits independent of weight loss, such as cardiovascular protection for semaglutide; average efficacy; and financial accessibility for patients.”

Predicting responders isn’t straightforward, said Robert Kushner, MD, professor of medicine and medical education at the Feinberg School of Medicine at Northwestern University and medical director of the Wellness Institute at Northwestern Memorial Hospital in Chicago.

“Despite looking at baseline demographic data such as race, ethnicity, age, weight, and BMI, we are unable to predict who will lose more or less weight,” he told GI & Hepatology News. The one exception is that women generally lose more weight than men. “However, even among females, we cannot discern which females will lose more weight than other females,” he said.

If an individual is not showing sufficient weight loss on a particular medication, “we first explore potential reasons that can be addressed, such as the patient is not taking the medication or is skipping doses,” Kushner said. If need be, they discuss changing to a different drug to improve compliance. He also stresses the importance of making lifestyle changes in diet and physical activity for patients taking AOMs.

Often patients who do not lose at least 5% of their weight within 3 months are not likely to respond well to that medication even if they remain on it. “So, early response rates determine longer-term success,” Kushner said.

Acosta said that if a patient isn’t responding to one class of medication, he pivots to a treatment better aligned with their phenotype. “That could mean switching from a GLP-1 to a medication like [naltrexone/bupropion] or trying a new method altogether,” he said. “The key is that the treatment decision is rooted in the patient’s biology, not just a reaction to short-term results. We also emphasize the importance of long-term follow-up and support.”

The goal isn’t just weight loss but also improved health and quality of life, Acosta said. “Whether through medication, surgery, or behavior change, what matters most is tailoring the care plan to each individual’s unique biology and needs.”

The new study received support from the Mayo Clinic Clinical Research Trials Unit, Vivus Inc., and Phenomix Sciences. Acosta is supported by a National Institutes of Health grant.

Acosta is a co-founder and inventor of intellectual property licensed to Phenomix Sciences Inc.; has served as a consultant for Rhythm Pharmaceuticals, Gila Therapeutics, Amgen, General Mills, Boehringer Ingelheim, Currax Pharmaceuticals, Nestlé, Bausch Health, and Rare Diseases; and has received research support or had contracts with Vivus Inc., Satiogen Pharmaceuticals, Boehringer Ingelheim, and Rhythm Pharmaceuticals. Machineni has been involved in semaglutide and tirzepatide clinical trials and has been a consultant to Novo Nordisk, Eli Lilly and Company, and Rhythm Pharmaceuticals. Kushner is on the scientific advisory board for Novo Nordisk.

A version of this article appeared on Medscape.com.

Emerging research indicates that phenotype-based testing may help identify which biologic process is driving an individual’s obesity, enabling clinicians to better tailor antiobesity medication (AOM) to the patient.

Currently, patient response to AOMs varies widely, with some patients responding robustly to AOMs and others responding weakly or not at all.

For example, trials of the GLP-1 semaglutide found that 32%-39.6% of people are “super responders,” achieving weight loss in excess of 20%, and a subgroup of 10.2%-16.7% of individuals are nonresponders. Similar variability was found with other AOMs, including the GLP-1 liraglutide and tirzepatide, a dual GLP-1/glucose-dependent insulinotropic polypeptide receptor agonist.

Studies of semaglutide suggest that people with obesity and type 2 diabetes (T2D) lose less weight on the drug than those without T2D, and men tend to lose less weight than women.

However, little else is known about predictors of response rates for various AOMs, and medication selection is typically based on patient or physician preference, comorbidities, medication interactions, and insurance coverage.

Although definitions of a “nonresponder” vary, the Endocrine Society’s latest guideline, which many clinicians follow, states that an AOM is considered effective if patients lose more than 5% of their body weight within 3 months.

Can nonresponders and lower responders be identified and helped? Yes, but it’s complicated.

“Treating obesity effectively means recognizing that not all patients respond the same way to the same treatment, and that’s not a failure; it’s a signal,” said Andres Acosta, MD, PhD, an obesity expert at Mayo Clinic, Rochester, Minnesota, and a cofounder of Phenomix Sciences, a biotech company in Menlo Park, California.

“Obesity is not a single disease. It’s a complex, multifactorial condition driven by diverse biological pathways,” he told GI & Hepatology News. “Semaglutide and other GLP-1s primarily act by reducing appetite and slowing gastric emptying, but not all patients have obesity that is primarily driven by appetite dysregulation.”

 

Phenotype-Based Profiling

Figuring out what drives an individual’s obesity is where a phenotype-based profiling test could possibly help.

Acosta and colleagues previously used a variety of validated studies and questionnaires to identify four phenotypes that represent distinct biologic drivers of obesity: hungry brain (abnormal satiation), emotional hunger (hedonic eating), hungry gut (abnormal satiety), and slow burn (decreased metabolic rate). In their pragmatic clinical trial, phenotype-guided AOM selection was associated with 1.75-fold greater weight loss after 12 months than the standard approach to drug selection, with mean weight loss of 15.9% and 9%, respectively.

“If a patient’s obesity isn’t primarily rooted in the mechanisms targeted by a particular drug, their response will naturally be limited,” Acosta said. “It’s not that they’re failing the medication; the medication simply isn’t the right match for their biology.”

For their new study, published online in Cell Metabolism, Acosta and colleagues built on their previous research by analyzing the genetic and nongenetic factors that influenced calories needed to reach satiation (Calories to Satiation [CTS]) in adults with obesity. They then used machine learning techniques to develop a CTS gene risk score (CTS-GRS) that could be measured by a DNA saliva test.

The study included 717 adults with obesity (mean age, 41; 75% women) with marked variability in satiation, ranging from 140 to 2166 kcals to reach satiation.

CTS was assessed through an ad libitum meal, combined with physiological and behavioral evaluations, including calorimetry, imaging, blood sampling, and gastric emptying tests. The largest contributors to CTS variability were sex and genetic factors, while other anthropometric measurements played lesser roles.

Various analyses and assessments of participants’ CTS-GRS scores showed that individuals with a high CTS-GRS, or hungry brain phenotype, experienced significantly greater weight loss when treated with phentermine/topiramate than those with a low CTS-GRS, or hungry gut, phenotype. After 52 weeks of treatment, individuals with the hungry brain phenotype lost an average of 17.4% of their body weight compared with 11.2% in those with the hungry gut phenotype.

An analysis of a separate 16-week study showed that patients with the hungry gut phenotype responded better to the GLP-1 liraglutide, losing 6.4% total body weight, compared to 3.3% for those with the hungry brain phenotype.

Overall, the CTS-GRS test predicted drug response with up to 84% accuracy (area under the curve, 0.76 in men and 0.84 in women). The authors acknowledged that these results need to be replicated prospectively and in more diverse populations to validate the test’s predictive ability.

“This kind of phenotype-based profiling allows us to predict which patients are more likely to respond and who might need a different intervention,” Acosta said. “It’s a critical step toward eliminating trial-and-error in obesity treatment.”

The test (MyPhenome test) is used at more than 80 healthcare clinics in the United States, according to Phenomix Sciences, which manufactures it. A company spokesperson said the test does not require FDA approval because it is used to predict obesity phenotypes to help inform treatment, but not to identify specific medications or other interventions. “If it were to do the latter,” the spokesperson said, “it would be considered a ‘companion diagnostic’ and subject to the FDA clearance process.”

 

What to Do if an AOM Isn’t Working?

It’s one thing to predict whether an individual might do better on one drug vs another, but what should clinicians do meanwhile to optimize weight loss for their patients who may be struggling on a particular drug?

“Efforts to predict the response to GLP-1 therapy have been a hot topic,” noted Sriram Machineni, MD, associate professor at Montefiore Medical Center, Bronx, New York, and founding director of the Fleischer Institute Medical Weight Center at Montefiore Einstein. Although the current study showed that genetic testing could predict responders, like Acosta, he agreed that the results need to be replicated in a prospective manner.

“In the absence of a validated tool for predicting response to specific medications, we use a prioritization process for trialing medications,” Machineni told GI & Hepatology News. “The prioritization is based on the suitability of the side-effect profile to the specific patient, including contraindications; benefits independent of weight loss, such as cardiovascular protection for semaglutide; average efficacy; and financial accessibility for patients.”

Predicting responders isn’t straightforward, said Robert Kushner, MD, professor of medicine and medical education at the Feinberg School of Medicine at Northwestern University and medical director of the Wellness Institute at Northwestern Memorial Hospital in Chicago.

“Despite looking at baseline demographic data such as race, ethnicity, age, weight, and BMI, we are unable to predict who will lose more or less weight,” he told GI & Hepatology News. The one exception is that women generally lose more weight than men. “However, even among females, we cannot discern which females will lose more weight than other females,” he said.

If an individual is not showing sufficient weight loss on a particular medication, “we first explore potential reasons that can be addressed, such as the patient is not taking the medication or is skipping doses,” Kushner said. If need be, they discuss changing to a different drug to improve compliance. He also stresses the importance of making lifestyle changes in diet and physical activity for patients taking AOMs.

Often patients who do not lose at least 5% of their weight within 3 months are not likely to respond well to that medication even if they remain on it. “So, early response rates determine longer-term success,” Kushner said.

Acosta said that if a patient isn’t responding to one class of medication, he pivots to a treatment better aligned with their phenotype. “That could mean switching from a GLP-1 to a medication like [naltrexone/bupropion] or trying a new method altogether,” he said. “The key is that the treatment decision is rooted in the patient’s biology, not just a reaction to short-term results. We also emphasize the importance of long-term follow-up and support.”

The goal isn’t just weight loss but also improved health and quality of life, Acosta said. “Whether through medication, surgery, or behavior change, what matters most is tailoring the care plan to each individual’s unique biology and needs.”

The new study received support from the Mayo Clinic Clinical Research Trials Unit, Vivus Inc., and Phenomix Sciences. Acosta is supported by a National Institutes of Health grant.

Acosta is a co-founder and inventor of intellectual property licensed to Phenomix Sciences Inc.; has served as a consultant for Rhythm Pharmaceuticals, Gila Therapeutics, Amgen, General Mills, Boehringer Ingelheim, Currax Pharmaceuticals, Nestlé, Bausch Health, and Rare Diseases; and has received research support or had contracts with Vivus Inc., Satiogen Pharmaceuticals, Boehringer Ingelheim, and Rhythm Pharmaceuticals. Machineni has been involved in semaglutide and tirzepatide clinical trials and has been a consultant to Novo Nordisk, Eli Lilly and Company, and Rhythm Pharmaceuticals. Kushner is on the scientific advisory board for Novo Nordisk.

A version of this article appeared on Medscape.com.

Low rates of retained gastric contents were seen in endoscopy patients on GLP-1 receptor agonists ( RAs), a retrospective multicenter cross-sectional analysis reported in The American Journal of Gastroenterology. Moreover, most instances occurred in patients using the drugs for type 2 diabetes (T2D) rather than for weight loss alone.

The findings suggest adopting an individualized approach rather than universal preoperative withholding of GLP-1 RAs before endoscopy, concluded Jennifer Phan, MD, medical director of the Hoag Advanced Endoscopy Center in Newport Beach, California, and colleagues. These agents are associated with slowed gastric emptying, possibly raising the risk for pulmonary aspiration. The study identified comorbid uncontrolled T2D as a risk factor for retained gastric contents.

Recommendations from gastroenterological societies and the American Society of Anesthesiologists (ASA) differ regarding pre-endoscopic holding of these ubiquitous agents used for obesity and T2D. “Many patients undergo routine endoscopic procedures, and there was concern from the anesthesia safety perspective for retained gastric contents,” Phan told GI & Hepatology News. “At first these events were seen in a handful of cases; however, out of precaution this resulted in a statement from the ASA recommending that patients hold their GLP-1 medications for at least 1 week prior to a routine endoscopic procedure.”

That guidance resulted in protocol changes within endoscopy units, cancelled procedures, and potential delays in patient care. “We wanted to study whether this concern was clinically valid and to help identify which subgroup of patients are at highest risk in order to best inform anesthesia and endoscopy practices,” Phan added.

The ASA updated its guidance in 2023.

The current study aligns with other research showing that rates of clinically relevant retained gastric contents are < 10%, Phan said. For instance, the American Gastroenterological Association (AGA) published a rapid clinical practice update in November 2023 that found insufficient evidence to support patients stopping the medications before endoscopic procedures. AGA guidance suggests an individual approach for each patient on a GLP-1 RA rather than a blanket statement on how to manage all patients taking the medications.

“Our initial hypothesis was that the rates of clinically relevant retained gastric contents in patients on GLP-1 RA medications would be low,” Phan noted. “This was born out of anecdotal experience of the limited number of aborted procedures we experienced before the ASA statement.” 

Her group also hypothesized that the indication for which the GLP-1 RA was prescribed would be important, with patients taking GLP-1 RA medications for diabetes potentially having a higher likelihood of retained contents given the concomitant propensity for delayed gastric motility related to uncontrolled hyperglycemia.

 

The Study

The investigators identified 815 patients on confirmed GLP-1 RA medications of various types receiving endoscopy from 2021 to 2023 at four centers. Demographics, prescribing practices, and procedure outcomes were captured. GLP-1 RA management of preoperative holding was retroactively classified per ASA guidance.

Of the 815 patients (mean age, 67.7 years; 57.7% women; 53.9% White individuals), 70 (8.7%) exhibited retained gastric contents on endoscopy. Of these 65 (93%) had T2D with a median A1c of 6.5%. Among those with retained contents, most had a minimal (10, 14.3%) or moderate (31, 44.3%) amount of food retained, although 29 (41.4%) had a large quantity. Only one patient required unplanned intubation because of a large quantity of residual content, and none had aspiration events.

In multivariate analysis, the odds ratio of retention in those with diabetes was 4.1. “Given the predominance of diabetes in those with retained gastric contents, we highlight the potential to risk-stratify patients who require further preprocedural consideration,” the authors wrote.

Those with GLP-1 RA held per ASA guidance (406, 49.8%) were less likely to have retained contents (4.4% vs 12.7%; P < .001), but no significant differences for intubation (0% vs 2%; P = .53) or aborting procedure rates (28% vs 18%; P = .40) due to gastric retention were observed.

On multivariable analysis, the likelihood of food retention increased by 36% (95% CI, 1.15-1.60) for every 1% increase in glycosylated hemoglobin after adjusting for GLP-1 RA type and preoperative medication hold.

“Our study can help to differentiate which patients can be at largest risk for retained gastric contents,” Phan said, noting the impact of increasing percentages of A1C. “There’s a 36% increased likelihood of food retention in patients on GLP-1 medications, so a blanket policy to hold GLP-1s in patients who are nondiabetic and taking the medication for obesity may not be the best approach. But if patients have uncontrolled hyperglycemia, then an approach of caution is clinically valid.” In that context, holding the GLP-1 RA injection or lengthening the preoperative clear-liquid diet policy should be considered.

She noted that the study results are generalizable because the study was conducted across multiple types of hospital systems, both university and county, and included all types of GLP-1 RA.

Offering an anesthesiologist’s perspective on the study, Paul Potnuru, MD, an assistant professor in the Department of Anesthesiology, Critical Care, and Pain Medicine at UTHealth Houston and not involved in the study, called the findings “somewhat reassuring” but said the risk for aspiration was still a consideration.

A recent review, however, reported that the risk for GLP-1 RA-associated pulmonary aspiration was low.

Potnuru acknowledged that the original ASA guidance on preoperative GLP-1 RA cessation led to some confusion. “There were not a lot of data on the issue, but some studies found that even with stopping GLP-1s 2 weeks preoperatively some patients still retained gastric content,” he told GI & Hepatology News.

A study at his center recently reported that 56% of GLP-1 RA users had increased pre-anesthesia residual gastric content compared with 19% of nonusers.

From the anesthesiologist’s clinical vantage point, the margin of safety is an issue even if aspiration risk is low. “If there’s a 1 in 1000 chance or even a 1 in 3000 chance, that can be considered too high,” Potnuru said.

He further noted that the current study included only 815 patients, not nearly enough for definitive data. In addition, a retrospective study based on medical records can’t really capture all the real-world procedural changes made in the operating room. “It’s common for anesthesiologists not to document all cases of intubation, for example,” he said.

While the ideal is a completely empty stomach, he agreed that a practical alternative to stopping GLP-1 RA therapy, especially that prescribed for diabetes, would be a 24-hour liquid diet, which would clear the stomach quickly. “If you stop these drugs in patients taking them for diabetes, you get a worsening of their glycemic control,” he said.

He noted that patients have different risk tolerances, with some willing to go ahead even if ultrasound shows gastric retention, while some opt to cancel.

Prospective studies are needed, Potnuru added, “because you find more if you know what you’re looking for.” His center is starting a clinical trial in 150 patients to assess the impact of a 24-hour, liquids-only diet on gastric retention.

According to Phan, other research is following GLP-1 RA users undergoing colonoscopy. “Future studies can look at the added value of point-of-care abdominal ultrasound to see if it increases precision preoperative management in these patients on GLP-1 medications.”

Other groups are examining the safety of these agents in the general context of sedation. “It’s worth noting that the studies are being done on currently available medications and may not apply to future medications such as triple agonists or anti-amylins that may come on the market in the near future,” Phan said.

This study received no financial support. Neither the study authors nor Potnuru had any conflicts of interest.

A version of this article appeared on Medscape.com.

Low rates of retained gastric contents were seen in endoscopy patients on GLP-1 receptor agonists ( RAs), a retrospective multicenter cross-sectional analysis reported in The American Journal of Gastroenterology. Moreover, most instances occurred in patients using the drugs for type 2 diabetes (T2D) rather than for weight loss alone.

The findings suggest adopting an individualized approach rather than universal preoperative withholding of GLP-1 RAs before endoscopy, concluded Jennifer Phan, MD, medical director of the Hoag Advanced Endoscopy Center in Newport Beach, California, and colleagues. These agents are associated with slowed gastric emptying, possibly raising the risk for pulmonary aspiration. The study identified comorbid uncontrolled T2D as a risk factor for retained gastric contents.

Recommendations from gastroenterological societies and the American Society of Anesthesiologists (ASA) differ regarding pre-endoscopic holding of these ubiquitous agents used for obesity and T2D. “Many patients undergo routine endoscopic procedures, and there was concern from the anesthesia safety perspective for retained gastric contents,” Phan told GI & Hepatology News. “At first these events were seen in a handful of cases; however, out of precaution this resulted in a statement from the ASA recommending that patients hold their GLP-1 medications for at least 1 week prior to a routine endoscopic procedure.”

That guidance resulted in protocol changes within endoscopy units, cancelled procedures, and potential delays in patient care. “We wanted to study whether this concern was clinically valid and to help identify which subgroup of patients are at highest risk in order to best inform anesthesia and endoscopy practices,” Phan added.

The ASA updated its guidance in 2023.

The current study aligns with other research showing that rates of clinically relevant retained gastric contents are < 10%, Phan said. For instance, the American Gastroenterological Association (AGA) published a rapid clinical practice update in November 2023 that found insufficient evidence to support patients stopping the medications before endoscopic procedures. AGA guidance suggests an individual approach for each patient on a GLP-1 RA rather than a blanket statement on how to manage all patients taking the medications.

“Our initial hypothesis was that the rates of clinically relevant retained gastric contents in patients on GLP-1 RA medications would be low,” Phan noted. “This was born out of anecdotal experience of the limited number of aborted procedures we experienced before the ASA statement.” 

Her group also hypothesized that the indication for which the GLP-1 RA was prescribed would be important, with patients taking GLP-1 RA medications for diabetes potentially having a higher likelihood of retained contents given the concomitant propensity for delayed gastric motility related to uncontrolled hyperglycemia.

 

The Study

The investigators identified 815 patients on confirmed GLP-1 RA medications of various types receiving endoscopy from 2021 to 2023 at four centers. Demographics, prescribing practices, and procedure outcomes were captured. GLP-1 RA management of preoperative holding was retroactively classified per ASA guidance.

Of the 815 patients (mean age, 67.7 years; 57.7% women; 53.9% White individuals), 70 (8.7%) exhibited retained gastric contents on endoscopy. Of these 65 (93%) had T2D with a median A1c of 6.5%. Among those with retained contents, most had a minimal (10, 14.3%) or moderate (31, 44.3%) amount of food retained, although 29 (41.4%) had a large quantity. Only one patient required unplanned intubation because of a large quantity of residual content, and none had aspiration events.

In multivariate analysis, the odds ratio of retention in those with diabetes was 4.1. “Given the predominance of diabetes in those with retained gastric contents, we highlight the potential to risk-stratify patients who require further preprocedural consideration,” the authors wrote.

Those with GLP-1 RA held per ASA guidance (406, 49.8%) were less likely to have retained contents (4.4% vs 12.7%; P < .001), but no significant differences for intubation (0% vs 2%; P = .53) or aborting procedure rates (28% vs 18%; P = .40) due to gastric retention were observed.

On multivariable analysis, the likelihood of food retention increased by 36% (95% CI, 1.15-1.60) for every 1% increase in glycosylated hemoglobin after adjusting for GLP-1 RA type and preoperative medication hold.

“Our study can help to differentiate which patients can be at largest risk for retained gastric contents,” Phan said, noting the impact of increasing percentages of A1C. “There’s a 36% increased likelihood of food retention in patients on GLP-1 medications, so a blanket policy to hold GLP-1s in patients who are nondiabetic and taking the medication for obesity may not be the best approach. But if patients have uncontrolled hyperglycemia, then an approach of caution is clinically valid.” In that context, holding the GLP-1 RA injection or lengthening the preoperative clear-liquid diet policy should be considered.

She noted that the study results are generalizable because the study was conducted across multiple types of hospital systems, both university and county, and included all types of GLP-1 RA.

Offering an anesthesiologist’s perspective on the study, Paul Potnuru, MD, an assistant professor in the Department of Anesthesiology, Critical Care, and Pain Medicine at UTHealth Houston and not involved in the study, called the findings “somewhat reassuring” but said the risk for aspiration was still a consideration.

A recent review, however, reported that the risk for GLP-1 RA-associated pulmonary aspiration was low.

Potnuru acknowledged that the original ASA guidance on preoperative GLP-1 RA cessation led to some confusion. “There were not a lot of data on the issue, but some studies found that even with stopping GLP-1s 2 weeks preoperatively some patients still retained gastric content,” he told GI & Hepatology News.

A study at his center recently reported that 56% of GLP-1 RA users had increased pre-anesthesia residual gastric content compared with 19% of nonusers.

From the anesthesiologist’s clinical vantage point, the margin of safety is an issue even if aspiration risk is low. “If there’s a 1 in 1000 chance or even a 1 in 3000 chance, that can be considered too high,” Potnuru said.

He further noted that the current study included only 815 patients, not nearly enough for definitive data. In addition, a retrospective study based on medical records can’t really capture all the real-world procedural changes made in the operating room. “It’s common for anesthesiologists not to document all cases of intubation, for example,” he said.

While the ideal is a completely empty stomach, he agreed that a practical alternative to stopping GLP-1 RA therapy, especially that prescribed for diabetes, would be a 24-hour liquid diet, which would clear the stomach quickly. “If you stop these drugs in patients taking them for diabetes, you get a worsening of their glycemic control,” he said.

He noted that patients have different risk tolerances, with some willing to go ahead even if ultrasound shows gastric retention, while some opt to cancel.

Prospective studies are needed, Potnuru added, “because you find more if you know what you’re looking for.” His center is starting a clinical trial in 150 patients to assess the impact of a 24-hour, liquids-only diet on gastric retention.

According to Phan, other research is following GLP-1 RA users undergoing colonoscopy. “Future studies can look at the added value of point-of-care abdominal ultrasound to see if it increases precision preoperative management in these patients on GLP-1 medications.”

Other groups are examining the safety of these agents in the general context of sedation. “It’s worth noting that the studies are being done on currently available medications and may not apply to future medications such as triple agonists or anti-amylins that may come on the market in the near future,” Phan said.

This study received no financial support. Neither the study authors nor Potnuru had any conflicts of interest.

A version of this article appeared on Medscape.com.

Low rates of retained gastric contents were seen in endoscopy patients on GLP-1 receptor agonists ( RAs), a retrospective multicenter cross-sectional analysis reported in The American Journal of Gastroenterology. Moreover, most instances occurred in patients using the drugs for type 2 diabetes (T2D) rather than for weight loss alone.

The findings suggest adopting an individualized approach rather than universal preoperative withholding of GLP-1 RAs before endoscopy, concluded Jennifer Phan, MD, medical director of the Hoag Advanced Endoscopy Center in Newport Beach, California, and colleagues. These agents are associated with slowed gastric emptying, possibly raising the risk for pulmonary aspiration. The study identified comorbid uncontrolled T2D as a risk factor for retained gastric contents.

Recommendations from gastroenterological societies and the American Society of Anesthesiologists (ASA) differ regarding pre-endoscopic holding of these ubiquitous agents used for obesity and T2D. “Many patients undergo routine endoscopic procedures, and there was concern from the anesthesia safety perspective for retained gastric contents,” Phan told GI & Hepatology News. “At first these events were seen in a handful of cases; however, out of precaution this resulted in a statement from the ASA recommending that patients hold their GLP-1 medications for at least 1 week prior to a routine endoscopic procedure.”

That guidance resulted in protocol changes within endoscopy units, cancelled procedures, and potential delays in patient care. “We wanted to study whether this concern was clinically valid and to help identify which subgroup of patients are at highest risk in order to best inform anesthesia and endoscopy practices,” Phan added.

The ASA updated its guidance in 2023.

The current study aligns with other research showing that rates of clinically relevant retained gastric contents are < 10%, Phan said. For instance, the American Gastroenterological Association (AGA) published a rapid clinical practice update in November 2023 that found insufficient evidence to support patients stopping the medications before endoscopic procedures. AGA guidance suggests an individual approach for each patient on a GLP-1 RA rather than a blanket statement on how to manage all patients taking the medications.

“Our initial hypothesis was that the rates of clinically relevant retained gastric contents in patients on GLP-1 RA medications would be low,” Phan noted. “This was born out of anecdotal experience of the limited number of aborted procedures we experienced before the ASA statement.” 

Her group also hypothesized that the indication for which the GLP-1 RA was prescribed would be important, with patients taking GLP-1 RA medications for diabetes potentially having a higher likelihood of retained contents given the concomitant propensity for delayed gastric motility related to uncontrolled hyperglycemia.

 

The Study

The investigators identified 815 patients on confirmed GLP-1 RA medications of various types receiving endoscopy from 2021 to 2023 at four centers. Demographics, prescribing practices, and procedure outcomes were captured. GLP-1 RA management of preoperative holding was retroactively classified per ASA guidance.

Of the 815 patients (mean age, 67.7 years; 57.7% women; 53.9% White individuals), 70 (8.7%) exhibited retained gastric contents on endoscopy. Of these 65 (93%) had T2D with a median A1c of 6.5%. Among those with retained contents, most had a minimal (10, 14.3%) or moderate (31, 44.3%) amount of food retained, although 29 (41.4%) had a large quantity. Only one patient required unplanned intubation because of a large quantity of residual content, and none had aspiration events.

In multivariate analysis, the odds ratio of retention in those with diabetes was 4.1. “Given the predominance of diabetes in those with retained gastric contents, we highlight the potential to risk-stratify patients who require further preprocedural consideration,” the authors wrote.

Those with GLP-1 RA held per ASA guidance (406, 49.8%) were less likely to have retained contents (4.4% vs 12.7%; P < .001), but no significant differences for intubation (0% vs 2%; P = .53) or aborting procedure rates (28% vs 18%; P = .40) due to gastric retention were observed.

On multivariable analysis, the likelihood of food retention increased by 36% (95% CI, 1.15-1.60) for every 1% increase in glycosylated hemoglobin after adjusting for GLP-1 RA type and preoperative medication hold.

“Our study can help to differentiate which patients can be at largest risk for retained gastric contents,” Phan said, noting the impact of increasing percentages of A1C. “There’s a 36% increased likelihood of food retention in patients on GLP-1 medications, so a blanket policy to hold GLP-1s in patients who are nondiabetic and taking the medication for obesity may not be the best approach. But if patients have uncontrolled hyperglycemia, then an approach of caution is clinically valid.” In that context, holding the GLP-1 RA injection or lengthening the preoperative clear-liquid diet policy should be considered.

She noted that the study results are generalizable because the study was conducted across multiple types of hospital systems, both university and county, and included all types of GLP-1 RA.

Offering an anesthesiologist’s perspective on the study, Paul Potnuru, MD, an assistant professor in the Department of Anesthesiology, Critical Care, and Pain Medicine at UTHealth Houston and not involved in the study, called the findings “somewhat reassuring” but said the risk for aspiration was still a consideration.

A recent review, however, reported that the risk for GLP-1 RA-associated pulmonary aspiration was low.

Potnuru acknowledged that the original ASA guidance on preoperative GLP-1 RA cessation led to some confusion. “There were not a lot of data on the issue, but some studies found that even with stopping GLP-1s 2 weeks preoperatively some patients still retained gastric content,” he told GI & Hepatology News.

A study at his center recently reported that 56% of GLP-1 RA users had increased pre-anesthesia residual gastric content compared with 19% of nonusers.

From the anesthesiologist’s clinical vantage point, the margin of safety is an issue even if aspiration risk is low. “If there’s a 1 in 1000 chance or even a 1 in 3000 chance, that can be considered too high,” Potnuru said.

He further noted that the current study included only 815 patients, not nearly enough for definitive data. In addition, a retrospective study based on medical records can’t really capture all the real-world procedural changes made in the operating room. “It’s common for anesthesiologists not to document all cases of intubation, for example,” he said.

While the ideal is a completely empty stomach, he agreed that a practical alternative to stopping GLP-1 RA therapy, especially that prescribed for diabetes, would be a 24-hour liquid diet, which would clear the stomach quickly. “If you stop these drugs in patients taking them for diabetes, you get a worsening of their glycemic control,” he said.

He noted that patients have different risk tolerances, with some willing to go ahead even if ultrasound shows gastric retention, while some opt to cancel.

Prospective studies are needed, Potnuru added, “because you find more if you know what you’re looking for.” His center is starting a clinical trial in 150 patients to assess the impact of a 24-hour, liquids-only diet on gastric retention.

According to Phan, other research is following GLP-1 RA users undergoing colonoscopy. “Future studies can look at the added value of point-of-care abdominal ultrasound to see if it increases precision preoperative management in these patients on GLP-1 medications.”

Other groups are examining the safety of these agents in the general context of sedation. “It’s worth noting that the studies are being done on currently available medications and may not apply to future medications such as triple agonists or anti-amylins that may come on the market in the near future,” Phan said.

This study received no financial support. Neither the study authors nor Potnuru had any conflicts of interest.

A version of this article appeared on Medscape.com.

WASHINGTON, DC — A low-emulsifier-containing diet led to a threefold increased likelihood of improvement in symptoms of Crohn’s disease compared with an emulsifier-containing diet in a randomized double-blind dietary trial involving 154 patients with mildly active disease living across the United Kingdom.

The findings were reported at Gut Microbiota for Health (GMFH) World Summit 2025 by Benoit Chassaing, PhD, of the Institut Pasteur, Paris, France, whose research leading up to the trial has demonstrated that food additive emulsifiers —ubiquitous in processed foods — alter microbiota composition and lead to microbiota encroachment into the mucus layer of the gut and subsequent chronic gut inflammation.

Patients in the ADDapt trial, which was also reported in an abstract earlier this year at the European Crohn’s and Colitis Organization (ECCO) 2025 Congress, had a Crohn’s disease activity index (CDAI) of 150-250 and evidence of inflammation (faecal calprotectin (FCP) ≥ 150 µg/g or endoscopy/radiology). All “had been exposed in their regular diets to emulsifiers,” said Chassaing, a co-investigator, during a GMFH session on “Dietary Drivers of Health and Disease.”

They were randomized to either a low-emulsifier diet or to a low-emulsifier diet followed by emulsifier “resupplementation” — a design meant to “account for the very strong placebo effect that is always observed with dietary studies,” he said.

All patients received dietary counseling, a smart phone app and barcode scan to support shopping, and weekly support. They also received supermarket foods for 25% of their needs that were either free of emulsifiers or contained emulsifiers, and they were provided three snacks per day that were emulsifier-free or contained carrageenan, carboxymethycellulse (CMC), and polysorbate-80 (P80) — dietary emulsifiers that are commonly added to processed foods to enhance texture and extend shelf-life.

In the intention-to-treat (ITT) analysis, 49% of patients in the intervention group reached the primary endpoint of a 70-point reduction or more in CDAI response after 8 weeks compared with 31% of those in the control group (P = .019), with an adjusted relative risk of response of 3.1 (P = .003), Chassaing shared at the GMFH meeting, convened by the American Gastroenterological Association and the European Society of Neurogastroenterology and Motility.

In the per-protocol analysis (n = 119), 61% and 47% of patients in the intervention and control groups, respectively, reached the primary outcome of CDAI response, with an adjusted relative risk of response of 3.0 (P = .018), he said.

Secondary endpoints included CDAI remission at 24 weeks, and according to the abstract for the ECCO Congress, in the ITT analysis, patients in the intervention group were more than twice as likely to experience remission.

Chassaing noted at the GMFH meeting that as part of the study, he and coinvestigators have been investigating the participants’ gut microbiota with metagenomic analyses. The study was led by Kevin Whelan, PhD, head of the Department of Nutritional Sciences at King’s College London, London, England.

 

Can Emulsifier-Sensitive Individuals Be Identified?

In murine model research 10 years ago, Chassaing showed that the administration of CMC and P80 results in microbiota encroachment into the mucus layer of the gut, alterations in microbiota composition — including an increase in bacteria that produce pro-inflammatory flagellin — and development of chronic inflammation.

Wild-type mice treated with these compounds developed metabolic disease, and mice that were modified to be predisposed to colitis had a higher incidence of robust colitis. Moreover, fecal transplantation from emulsifier-treated mice to germ-free mice reproduced these changes, “clearly suggesting that the microbiome itself is sufficient to drive chronic inflammation,” he said.

In recent years, in humans, analyses from the large French NutriNet-Sante prospective cohort study have shown associations between exposure to food additive emulsifiers and the risk for cardiovascular disease, the risk for cancer (overall, breast, and prostate), and the risk for type 2 diabetes.

But to explore causality and better understand the mechanisms of emulsifier-driven changes on the microbiota, Chassaing and his colleagues also launched the FRESH study (Functional Research on Emulsifier in Humans), a double-blind randomized controlled-feeding study of the emulsifier CMC. For 11 days, nine healthy patients consumed an emulsifier-free diet and 11 consumed an identical diet enriched with 15 g/d of CMC.

Patients on the CMC-containing diet had reduced microbiota diversity and depletions of an array of microbiota-related metabolites, but only a small subset had profound alterations in microbiota composition and increased microbiota encroachment into the mucus layer. “Some seemed to be resistant to CMC-induced microbiota encroachment, while some were highly susceptible,” Chassaing said.

The pilot study raised the question, he said, of whether there is an “infectivity component” — some kind of “sensitive” gut microbiota composition — that may be associated with dietary emulsifier-driven inflammation and disease.

In other murine research, Chassaing and his team found that germ-free mice colonized with Crohn’s disease-associated adherent-invasive E coli (AIEC) and subsequently given CMC or P80 developed chronic inflammation and metabolic dysregulation, “clearly demonstrating that you can convert resistant mice to sensitive mice just by adding one bacteria to the ecosystem,” he said. “The presence of AIEC alone was sufficient to drive the detrimental effects of dietary emulsifiers.”

(In vitro research with transcriptomic analysis then showed that the emulsifiers directly elicit AIEC virulence gene expression, Chassaing and his coauthors wrote in their 2020 paper, facilitating AIEC’s “penetration of the mucus layer and adherence to epithelial cells and resulting in activation of host pro-inflammatory signaling.”)

“We don’t think it’s solely the AIEC bacteria that will drive emulsifier sensitivity, though…we think it’s more complex,” Chassaing said at the meeting. Overall, the findings raise the question of whether emulsifier-sensitive individuals can be identified.

This, he said, is one of his most recent research questions. His lab has led the development of an in vitro microbiota model built to predict an individual’s sensitivity to emulsifiers. In a study published in April, the model recapitulated the differential CMC sensitivity observed in the earlier FRESH study, suggesting that an individual’s sensitivity to emulsifiers can indeed be predicted by examining their baseline microbiota.

 

Interpreting the Epidemiology

Chassaing’s research arch illustrates the synergy between epidemiological research, basic/translational research, and clinical interventional research that’s needed to understand the diet-microbiome intersection in inflammatory bowel disease, said Ashwin Ananthakrishnan, MBBS, MPH, AGAF, associate professor of medicine at Massachusetts General Hospital, Boston, in an interview at the meeting.

“It’s a good example of how to really span the spectrum, starting from the big picture and going deeper to understand mechanisms, and starting from mechanisms and expanding it out,” Ananthakrishnan said.

In his own talk about research on IBD, Ananthakrishnan said that epidemiological data have shown over the past 10-15 years that total dietary fiber is inversely associated with the risk for Crohn’s disease (with the strongest associations with fiber from fruits and vegetables). Studies have also shown that a higher intake of polyunsaturated fatty acids is associated with a lower risk for ulcerative colitis, whereas “an n-6-fatty acid-rich diet is associated with a higher risk of ulcerative colitis,” he said.

Dietary cohort studies, meanwhile, have shed light on the influence of dietary patterns — such as the Mediterranean diet and diets with high inflammatory potential—on IBD. A diet rich in ultra-processed foods has also been shown in a prospective cohort study to be associated with a higher risk for Crohn’s disease, with certain categories of ultra-processed foods (eg, breads and breakfast foods) having the strongest associations.

Such studies are limited in part, however, by inadequate assessment of potentially relevant variables such as emulsifiers, preservatives, and how the food is processed, he said.

And in interpreting the epidemiological research on fiber and IBD, for instance, one must appreciate that “there are a number of mechanisms by which fiber is impactful…there’s a big picture to look at,” Ananthakrishnan said. Fiber “can affect the microbiome, clearly, it can affect the gut barrier, and it can affect bile acids, and there are detailed translational studies in support of each of these.”

But there are other constituents of fruits and vegetables “that could potentially influence disease risk, such as AhR ligands and polyphenols,” he said. “And importantly, people not eating a lot of fiber may be eating a lot of ultra-processed foods.”

Most interventional studies of fiber have not shown a benefit of a high-fiber diet, Ananthakrishnan said, but there are multiple possible reasons and factors at play, including potential population differences (eg, in inflammatory status or baseline microbiota), shortcomings of the interventions, and potentially inaccurate outcomes.

Abigail Johnson, PhD, RDN, associate director of the Nutrition Coordinating Center, University of Minnesota Twin Cities, which supports dietary analysis, said during the session that the focus of dietary research is “moving toward understanding overall dietary patterns” as opposed to focusing more narrowly on vitamins, minerals, and macronutrients such as proteins, fats, and carbohydrates.

This is an improvement, though “we still don’t have good approaches for understanding [the contributions of] things like additives and emulsifiers, food preparation and cooking, and food processing,” said Johnson, assistant professor in the Division of Epidemiology and Community Health at University of Minnesota Twin Cities. “Perhaps by looking at things at the food level we can overcome some of these limitations.”

Ananthakrishnan reported being a consultant for Geneoscopy and receiving a research grant from Takeda. Chassaing did not report any financial disclosures. Johnson reported that she had no financial disclosures.

A version of this article appeared on Medscape.com.

WASHINGTON, DC — A low-emulsifier-containing diet led to a threefold increased likelihood of improvement in symptoms of Crohn’s disease compared with an emulsifier-containing diet in a randomized double-blind dietary trial involving 154 patients with mildly active disease living across the United Kingdom.

The findings were reported at Gut Microbiota for Health (GMFH) World Summit 2025 by Benoit Chassaing, PhD, of the Institut Pasteur, Paris, France, whose research leading up to the trial has demonstrated that food additive emulsifiers —ubiquitous in processed foods — alter microbiota composition and lead to microbiota encroachment into the mucus layer of the gut and subsequent chronic gut inflammation.

Patients in the ADDapt trial, which was also reported in an abstract earlier this year at the European Crohn’s and Colitis Organization (ECCO) 2025 Congress, had a Crohn’s disease activity index (CDAI) of 150-250 and evidence of inflammation (faecal calprotectin (FCP) ≥ 150 µg/g or endoscopy/radiology). All “had been exposed in their regular diets to emulsifiers,” said Chassaing, a co-investigator, during a GMFH session on “Dietary Drivers of Health and Disease.”

They were randomized to either a low-emulsifier diet or to a low-emulsifier diet followed by emulsifier “resupplementation” — a design meant to “account for the very strong placebo effect that is always observed with dietary studies,” he said.

All patients received dietary counseling, a smart phone app and barcode scan to support shopping, and weekly support. They also received supermarket foods for 25% of their needs that were either free of emulsifiers or contained emulsifiers, and they were provided three snacks per day that were emulsifier-free or contained carrageenan, carboxymethycellulse (CMC), and polysorbate-80 (P80) — dietary emulsifiers that are commonly added to processed foods to enhance texture and extend shelf-life.

In the intention-to-treat (ITT) analysis, 49% of patients in the intervention group reached the primary endpoint of a 70-point reduction or more in CDAI response after 8 weeks compared with 31% of those in the control group (P = .019), with an adjusted relative risk of response of 3.1 (P = .003), Chassaing shared at the GMFH meeting, convened by the American Gastroenterological Association and the European Society of Neurogastroenterology and Motility.

In the per-protocol analysis (n = 119), 61% and 47% of patients in the intervention and control groups, respectively, reached the primary outcome of CDAI response, with an adjusted relative risk of response of 3.0 (P = .018), he said.

Secondary endpoints included CDAI remission at 24 weeks, and according to the abstract for the ECCO Congress, in the ITT analysis, patients in the intervention group were more than twice as likely to experience remission.

Chassaing noted at the GMFH meeting that as part of the study, he and coinvestigators have been investigating the participants’ gut microbiota with metagenomic analyses. The study was led by Kevin Whelan, PhD, head of the Department of Nutritional Sciences at King’s College London, London, England.

 

Can Emulsifier-Sensitive Individuals Be Identified?

In murine model research 10 years ago, Chassaing showed that the administration of CMC and P80 results in microbiota encroachment into the mucus layer of the gut, alterations in microbiota composition — including an increase in bacteria that produce pro-inflammatory flagellin — and development of chronic inflammation.

Wild-type mice treated with these compounds developed metabolic disease, and mice that were modified to be predisposed to colitis had a higher incidence of robust colitis. Moreover, fecal transplantation from emulsifier-treated mice to germ-free mice reproduced these changes, “clearly suggesting that the microbiome itself is sufficient to drive chronic inflammation,” he said.

In recent years, in humans, analyses from the large French NutriNet-Sante prospective cohort study have shown associations between exposure to food additive emulsifiers and the risk for cardiovascular disease, the risk for cancer (overall, breast, and prostate), and the risk for type 2 diabetes.

But to explore causality and better understand the mechanisms of emulsifier-driven changes on the microbiota, Chassaing and his colleagues also launched the FRESH study (Functional Research on Emulsifier in Humans), a double-blind randomized controlled-feeding study of the emulsifier CMC. For 11 days, nine healthy patients consumed an emulsifier-free diet and 11 consumed an identical diet enriched with 15 g/d of CMC.

Patients on the CMC-containing diet had reduced microbiota diversity and depletions of an array of microbiota-related metabolites, but only a small subset had profound alterations in microbiota composition and increased microbiota encroachment into the mucus layer. “Some seemed to be resistant to CMC-induced microbiota encroachment, while some were highly susceptible,” Chassaing said.

The pilot study raised the question, he said, of whether there is an “infectivity component” — some kind of “sensitive” gut microbiota composition — that may be associated with dietary emulsifier-driven inflammation and disease.

In other murine research, Chassaing and his team found that germ-free mice colonized with Crohn’s disease-associated adherent-invasive E coli (AIEC) and subsequently given CMC or P80 developed chronic inflammation and metabolic dysregulation, “clearly demonstrating that you can convert resistant mice to sensitive mice just by adding one bacteria to the ecosystem,” he said. “The presence of AIEC alone was sufficient to drive the detrimental effects of dietary emulsifiers.”

(In vitro research with transcriptomic analysis then showed that the emulsifiers directly elicit AIEC virulence gene expression, Chassaing and his coauthors wrote in their 2020 paper, facilitating AIEC’s “penetration of the mucus layer and adherence to epithelial cells and resulting in activation of host pro-inflammatory signaling.”)

“We don’t think it’s solely the AIEC bacteria that will drive emulsifier sensitivity, though…we think it’s more complex,” Chassaing said at the meeting. Overall, the findings raise the question of whether emulsifier-sensitive individuals can be identified.

This, he said, is one of his most recent research questions. His lab has led the development of an in vitro microbiota model built to predict an individual’s sensitivity to emulsifiers. In a study published in April, the model recapitulated the differential CMC sensitivity observed in the earlier FRESH study, suggesting that an individual’s sensitivity to emulsifiers can indeed be predicted by examining their baseline microbiota.

 

Interpreting the Epidemiology

Chassaing’s research arch illustrates the synergy between epidemiological research, basic/translational research, and clinical interventional research that’s needed to understand the diet-microbiome intersection in inflammatory bowel disease, said Ashwin Ananthakrishnan, MBBS, MPH, AGAF, associate professor of medicine at Massachusetts General Hospital, Boston, in an interview at the meeting.

“It’s a good example of how to really span the spectrum, starting from the big picture and going deeper to understand mechanisms, and starting from mechanisms and expanding it out,” Ananthakrishnan said.

In his own talk about research on IBD, Ananthakrishnan said that epidemiological data have shown over the past 10-15 years that total dietary fiber is inversely associated with the risk for Crohn’s disease (with the strongest associations with fiber from fruits and vegetables). Studies have also shown that a higher intake of polyunsaturated fatty acids is associated with a lower risk for ulcerative colitis, whereas “an n-6-fatty acid-rich diet is associated with a higher risk of ulcerative colitis,” he said.

Dietary cohort studies, meanwhile, have shed light on the influence of dietary patterns — such as the Mediterranean diet and diets with high inflammatory potential—on IBD. A diet rich in ultra-processed foods has also been shown in a prospective cohort study to be associated with a higher risk for Crohn’s disease, with certain categories of ultra-processed foods (eg, breads and breakfast foods) having the strongest associations.

Such studies are limited in part, however, by inadequate assessment of potentially relevant variables such as emulsifiers, preservatives, and how the food is processed, he said.

And in interpreting the epidemiological research on fiber and IBD, for instance, one must appreciate that “there are a number of mechanisms by which fiber is impactful…there’s a big picture to look at,” Ananthakrishnan said. Fiber “can affect the microbiome, clearly, it can affect the gut barrier, and it can affect bile acids, and there are detailed translational studies in support of each of these.”

But there are other constituents of fruits and vegetables “that could potentially influence disease risk, such as AhR ligands and polyphenols,” he said. “And importantly, people not eating a lot of fiber may be eating a lot of ultra-processed foods.”

Most interventional studies of fiber have not shown a benefit of a high-fiber diet, Ananthakrishnan said, but there are multiple possible reasons and factors at play, including potential population differences (eg, in inflammatory status or baseline microbiota), shortcomings of the interventions, and potentially inaccurate outcomes.

Abigail Johnson, PhD, RDN, associate director of the Nutrition Coordinating Center, University of Minnesota Twin Cities, which supports dietary analysis, said during the session that the focus of dietary research is “moving toward understanding overall dietary patterns” as opposed to focusing more narrowly on vitamins, minerals, and macronutrients such as proteins, fats, and carbohydrates.

This is an improvement, though “we still don’t have good approaches for understanding [the contributions of] things like additives and emulsifiers, food preparation and cooking, and food processing,” said Johnson, assistant professor in the Division of Epidemiology and Community Health at University of Minnesota Twin Cities. “Perhaps by looking at things at the food level we can overcome some of these limitations.”

Ananthakrishnan reported being a consultant for Geneoscopy and receiving a research grant from Takeda. Chassaing did not report any financial disclosures. Johnson reported that she had no financial disclosures.

A version of this article appeared on Medscape.com.

WASHINGTON, DC — A low-emulsifier-containing diet led to a threefold increased likelihood of improvement in symptoms of Crohn’s disease compared with an emulsifier-containing diet in a randomized double-blind dietary trial involving 154 patients with mildly active disease living across the United Kingdom.

The findings were reported at Gut Microbiota for Health (GMFH) World Summit 2025 by Benoit Chassaing, PhD, of the Institut Pasteur, Paris, France, whose research leading up to the trial has demonstrated that food additive emulsifiers —ubiquitous in processed foods — alter microbiota composition and lead to microbiota encroachment into the mucus layer of the gut and subsequent chronic gut inflammation.

Patients in the ADDapt trial, which was also reported in an abstract earlier this year at the European Crohn’s and Colitis Organization (ECCO) 2025 Congress, had a Crohn’s disease activity index (CDAI) of 150-250 and evidence of inflammation (faecal calprotectin (FCP) ≥ 150 µg/g or endoscopy/radiology). All “had been exposed in their regular diets to emulsifiers,” said Chassaing, a co-investigator, during a GMFH session on “Dietary Drivers of Health and Disease.”

They were randomized to either a low-emulsifier diet or to a low-emulsifier diet followed by emulsifier “resupplementation” — a design meant to “account for the very strong placebo effect that is always observed with dietary studies,” he said.

All patients received dietary counseling, a smart phone app and barcode scan to support shopping, and weekly support. They also received supermarket foods for 25% of their needs that were either free of emulsifiers or contained emulsifiers, and they were provided three snacks per day that were emulsifier-free or contained carrageenan, carboxymethycellulse (CMC), and polysorbate-80 (P80) — dietary emulsifiers that are commonly added to processed foods to enhance texture and extend shelf-life.

In the intention-to-treat (ITT) analysis, 49% of patients in the intervention group reached the primary endpoint of a 70-point reduction or more in CDAI response after 8 weeks compared with 31% of those in the control group (P = .019), with an adjusted relative risk of response of 3.1 (P = .003), Chassaing shared at the GMFH meeting, convened by the American Gastroenterological Association and the European Society of Neurogastroenterology and Motility.

In the per-protocol analysis (n = 119), 61% and 47% of patients in the intervention and control groups, respectively, reached the primary outcome of CDAI response, with an adjusted relative risk of response of 3.0 (P = .018), he said.

Secondary endpoints included CDAI remission at 24 weeks, and according to the abstract for the ECCO Congress, in the ITT analysis, patients in the intervention group were more than twice as likely to experience remission.

Chassaing noted at the GMFH meeting that as part of the study, he and coinvestigators have been investigating the participants’ gut microbiota with metagenomic analyses. The study was led by Kevin Whelan, PhD, head of the Department of Nutritional Sciences at King’s College London, London, England.

 

Can Emulsifier-Sensitive Individuals Be Identified?

In murine model research 10 years ago, Chassaing showed that the administration of CMC and P80 results in microbiota encroachment into the mucus layer of the gut, alterations in microbiota composition — including an increase in bacteria that produce pro-inflammatory flagellin — and development of chronic inflammation.

Wild-type mice treated with these compounds developed metabolic disease, and mice that were modified to be predisposed to colitis had a higher incidence of robust colitis. Moreover, fecal transplantation from emulsifier-treated mice to germ-free mice reproduced these changes, “clearly suggesting that the microbiome itself is sufficient to drive chronic inflammation,” he said.

In recent years, in humans, analyses from the large French NutriNet-Sante prospective cohort study have shown associations between exposure to food additive emulsifiers and the risk for cardiovascular disease, the risk for cancer (overall, breast, and prostate), and the risk for type 2 diabetes.

But to explore causality and better understand the mechanisms of emulsifier-driven changes on the microbiota, Chassaing and his colleagues also launched the FRESH study (Functional Research on Emulsifier in Humans), a double-blind randomized controlled-feeding study of the emulsifier CMC. For 11 days, nine healthy patients consumed an emulsifier-free diet and 11 consumed an identical diet enriched with 15 g/d of CMC.

Patients on the CMC-containing diet had reduced microbiota diversity and depletions of an array of microbiota-related metabolites, but only a small subset had profound alterations in microbiota composition and increased microbiota encroachment into the mucus layer. “Some seemed to be resistant to CMC-induced microbiota encroachment, while some were highly susceptible,” Chassaing said.

The pilot study raised the question, he said, of whether there is an “infectivity component” — some kind of “sensitive” gut microbiota composition — that may be associated with dietary emulsifier-driven inflammation and disease.

In other murine research, Chassaing and his team found that germ-free mice colonized with Crohn’s disease-associated adherent-invasive E coli (AIEC) and subsequently given CMC or P80 developed chronic inflammation and metabolic dysregulation, “clearly demonstrating that you can convert resistant mice to sensitive mice just by adding one bacteria to the ecosystem,” he said. “The presence of AIEC alone was sufficient to drive the detrimental effects of dietary emulsifiers.”

(In vitro research with transcriptomic analysis then showed that the emulsifiers directly elicit AIEC virulence gene expression, Chassaing and his coauthors wrote in their 2020 paper, facilitating AIEC’s “penetration of the mucus layer and adherence to epithelial cells and resulting in activation of host pro-inflammatory signaling.”)

“We don’t think it’s solely the AIEC bacteria that will drive emulsifier sensitivity, though…we think it’s more complex,” Chassaing said at the meeting. Overall, the findings raise the question of whether emulsifier-sensitive individuals can be identified.

This, he said, is one of his most recent research questions. His lab has led the development of an in vitro microbiota model built to predict an individual’s sensitivity to emulsifiers. In a study published in April, the model recapitulated the differential CMC sensitivity observed in the earlier FRESH study, suggesting that an individual’s sensitivity to emulsifiers can indeed be predicted by examining their baseline microbiota.

 

Interpreting the Epidemiology

Chassaing’s research arch illustrates the synergy between epidemiological research, basic/translational research, and clinical interventional research that’s needed to understand the diet-microbiome intersection in inflammatory bowel disease, said Ashwin Ananthakrishnan, MBBS, MPH, AGAF, associate professor of medicine at Massachusetts General Hospital, Boston, in an interview at the meeting.

“It’s a good example of how to really span the spectrum, starting from the big picture and going deeper to understand mechanisms, and starting from mechanisms and expanding it out,” Ananthakrishnan said.

In his own talk about research on IBD, Ananthakrishnan said that epidemiological data have shown over the past 10-15 years that total dietary fiber is inversely associated with the risk for Crohn’s disease (with the strongest associations with fiber from fruits and vegetables). Studies have also shown that a higher intake of polyunsaturated fatty acids is associated with a lower risk for ulcerative colitis, whereas “an n-6-fatty acid-rich diet is associated with a higher risk of ulcerative colitis,” he said.

Dietary cohort studies, meanwhile, have shed light on the influence of dietary patterns — such as the Mediterranean diet and diets with high inflammatory potential—on IBD. A diet rich in ultra-processed foods has also been shown in a prospective cohort study to be associated with a higher risk for Crohn’s disease, with certain categories of ultra-processed foods (eg, breads and breakfast foods) having the strongest associations.

Such studies are limited in part, however, by inadequate assessment of potentially relevant variables such as emulsifiers, preservatives, and how the food is processed, he said.

And in interpreting the epidemiological research on fiber and IBD, for instance, one must appreciate that “there are a number of mechanisms by which fiber is impactful…there’s a big picture to look at,” Ananthakrishnan said. Fiber “can affect the microbiome, clearly, it can affect the gut barrier, and it can affect bile acids, and there are detailed translational studies in support of each of these.”

But there are other constituents of fruits and vegetables “that could potentially influence disease risk, such as AhR ligands and polyphenols,” he said. “And importantly, people not eating a lot of fiber may be eating a lot of ultra-processed foods.”

Most interventional studies of fiber have not shown a benefit of a high-fiber diet, Ananthakrishnan said, but there are multiple possible reasons and factors at play, including potential population differences (eg, in inflammatory status or baseline microbiota), shortcomings of the interventions, and potentially inaccurate outcomes.

Abigail Johnson, PhD, RDN, associate director of the Nutrition Coordinating Center, University of Minnesota Twin Cities, which supports dietary analysis, said during the session that the focus of dietary research is “moving toward understanding overall dietary patterns” as opposed to focusing more narrowly on vitamins, minerals, and macronutrients such as proteins, fats, and carbohydrates.

This is an improvement, though “we still don’t have good approaches for understanding [the contributions of] things like additives and emulsifiers, food preparation and cooking, and food processing,” said Johnson, assistant professor in the Division of Epidemiology and Community Health at University of Minnesota Twin Cities. “Perhaps by looking at things at the food level we can overcome some of these limitations.”

Ananthakrishnan reported being a consultant for Geneoscopy and receiving a research grant from Takeda. Chassaing did not report any financial disclosures. Johnson reported that she had no financial disclosures.

A version of this article appeared on Medscape.com.

Neighborhood-level social determinants of health (SDOH) are associated with the burden, comorbidities, and mortality of metabolic dysfunction-associated steatotic disease (MASLD). These health mediators should be considered along with individual SDOH in clinical care and healthcare quality and equity improvement, a large retrospective study of adults with MASLD at a multi-state healthcare institution concluded.

Across quartiles, patients in the most disadvantaged neighborhoods (according to home addresses) vs the least disadvantaged had worse outcomes and were also disproportionately Hispanic, Black, and Native American/Alaska Native, more often Spanish-speaking in primary language, and more often uninsured or on Medicaid, according to Karn Wijarnpreecha, MD, MPH, of the Division of Gastroenterology and Hepatology at University of Arizona College of Medicine–Phoenix, and colleagues writing in Clinical Gastroenterology and Hepatology.

Even after adjustment for measures in the Social Deprivation Index (SDI), the incidence of death, cirrhosis, diabetes mellitus (DM), and major adverse cardiovascular events (MACE) was higher in Native American/Alaska Native patients compared with their non-Hispanic White counterparts. The SDI is a composite measure of seven demographic characteristics from the American Community Survey, with scores ranging from 1 to 100 and weighted based on characteristics from national percentile rankings.

Aligning with the growing prevalence of obesity and DM, MASLD has increased substantially over the past three decades, and is now the leading cause of chronic liver disease in this country and the world. 

This rise in prevalence has underscored health disparities in MASLD and prompted research into linkd between liver disease and SDOH, defined as the conditions under which people are born, grow, live, work, and age. These are fundamental drivers of health disparities, including those in MASLD.
 

Study Details

Primary outcomes were MASLD burden, mortality, and comorbidities by neighborhood SDOH, assessed using the SDI in cross-sectional and longitudinal analyses.

A total of 69,191 adult patients (more than 50% female) diagnosed with MASLD were included, 45,003 of whom had at least 365 days of follow-up. They were treated from July 2012 to June 2023 in Banner Health Systems, a network that includes primary-, secondary-, and tertiary-care centers in Arizona, Colorado, Wyoming, Nevada, Nebraska, and California.

The median follow-up time was 48 months. Among patients across SDI quartiles (age range 49 to 62 years), 1390 patients (3.1%) died, 902 (2.0%) developed cirrhosis, 1087 (2.4%) developed LRE, 6537 (14.5%) developed DM, 2057 (4.6%) developed cancer, and 5409 (12.0%) developed MACE.

Those living in the most disadvantaged quartile of neighborhoods compared with the least had the following higher odds:

• cirrhosis, adjusted odds ratio [aOR], 1.42 (P < .001)
• any cardiovascular (CVD) disease, aOR, 1.20 (P < .001),
• coronary artery disease, aOR, 1.17 (P < .001)
• congestive heart failure, aOR, 1.43 (P < .001)
• cerebrovascular accident, aOR, 1.19 (P = .001)
• DM, aOR, 1.57 (P < .001)
• hypertension, aOR, 1.38 (P < .001).

They also had increased incidence of death (adjusted hazard ratio [aHR], 1.47; P < .001), LRE (aHR, 1.31; P = .012), DM (aHR, 1.47; P < .001), and MACE (aHR, 1.24; P < .001). 

The study expands upon previous SDOH-related research in liver disease and is the largest analysis of neighborhood-level SDOH in patients with MASLD to date. “Our findings are consistent with a recent study by Chen et al of over 15,900 patients with MASLD in Michigan that found neighborhood-level social disadvantage was associated with increased mortality and incident LREs and CVD,” Wijarnpreecha and colleagues wrote. 

“Beyond screening patients for individual-level SDOH, neighborhood-level determinants of health should also be considered, as they are important mediators between the environment and the individual,” they added, calling for studies to better understand the specific neighborhood SDOH that drive the disparate outcomes. In practice, integration of these measures into medical records might inform clinicians which patients would benefit from social services or help guide quality improvement projects and community partnerships.

Wijarnpreecha had no conflicts of interest to disclose. Several coauthors reported research support, consulting/advisory work, or stock ownership for various private-sector companies.
 

Neighborhood-level social determinants of health (SDOH) are associated with the burden, comorbidities, and mortality of metabolic dysfunction-associated steatotic disease (MASLD). These health mediators should be considered along with individual SDOH in clinical care and healthcare quality and equity improvement, a large retrospective study of adults with MASLD at a multi-state healthcare institution concluded.

Across quartiles, patients in the most disadvantaged neighborhoods (according to home addresses) vs the least disadvantaged had worse outcomes and were also disproportionately Hispanic, Black, and Native American/Alaska Native, more often Spanish-speaking in primary language, and more often uninsured or on Medicaid, according to Karn Wijarnpreecha, MD, MPH, of the Division of Gastroenterology and Hepatology at University of Arizona College of Medicine–Phoenix, and colleagues writing in Clinical Gastroenterology and Hepatology.

Even after adjustment for measures in the Social Deprivation Index (SDI), the incidence of death, cirrhosis, diabetes mellitus (DM), and major adverse cardiovascular events (MACE) was higher in Native American/Alaska Native patients compared with their non-Hispanic White counterparts. The SDI is a composite measure of seven demographic characteristics from the American Community Survey, with scores ranging from 1 to 100 and weighted based on characteristics from national percentile rankings.

Aligning with the growing prevalence of obesity and DM, MASLD has increased substantially over the past three decades, and is now the leading cause of chronic liver disease in this country and the world. 

This rise in prevalence has underscored health disparities in MASLD and prompted research into linkd between liver disease and SDOH, defined as the conditions under which people are born, grow, live, work, and age. These are fundamental drivers of health disparities, including those in MASLD.
 

Study Details

Primary outcomes were MASLD burden, mortality, and comorbidities by neighborhood SDOH, assessed using the SDI in cross-sectional and longitudinal analyses.

A total of 69,191 adult patients (more than 50% female) diagnosed with MASLD were included, 45,003 of whom had at least 365 days of follow-up. They were treated from July 2012 to June 2023 in Banner Health Systems, a network that includes primary-, secondary-, and tertiary-care centers in Arizona, Colorado, Wyoming, Nevada, Nebraska, and California.

The median follow-up time was 48 months. Among patients across SDI quartiles (age range 49 to 62 years), 1390 patients (3.1%) died, 902 (2.0%) developed cirrhosis, 1087 (2.4%) developed LRE, 6537 (14.5%) developed DM, 2057 (4.6%) developed cancer, and 5409 (12.0%) developed MACE.

Those living in the most disadvantaged quartile of neighborhoods compared with the least had the following higher odds:

• cirrhosis, adjusted odds ratio [aOR], 1.42 (P < .001)
• any cardiovascular (CVD) disease, aOR, 1.20 (P < .001),
• coronary artery disease, aOR, 1.17 (P < .001)
• congestive heart failure, aOR, 1.43 (P < .001)
• cerebrovascular accident, aOR, 1.19 (P = .001)
• DM, aOR, 1.57 (P < .001)
• hypertension, aOR, 1.38 (P < .001).

They also had increased incidence of death (adjusted hazard ratio [aHR], 1.47; P < .001), LRE (aHR, 1.31; P = .012), DM (aHR, 1.47; P < .001), and MACE (aHR, 1.24; P < .001). 

The study expands upon previous SDOH-related research in liver disease and is the largest analysis of neighborhood-level SDOH in patients with MASLD to date. “Our findings are consistent with a recent study by Chen et al of over 15,900 patients with MASLD in Michigan that found neighborhood-level social disadvantage was associated with increased mortality and incident LREs and CVD,” Wijarnpreecha and colleagues wrote. 

“Beyond screening patients for individual-level SDOH, neighborhood-level determinants of health should also be considered, as they are important mediators between the environment and the individual,” they added, calling for studies to better understand the specific neighborhood SDOH that drive the disparate outcomes. In practice, integration of these measures into medical records might inform clinicians which patients would benefit from social services or help guide quality improvement projects and community partnerships.

Wijarnpreecha had no conflicts of interest to disclose. Several coauthors reported research support, consulting/advisory work, or stock ownership for various private-sector companies.
 

Neighborhood-level social determinants of health (SDOH) are associated with the burden, comorbidities, and mortality of metabolic dysfunction-associated steatotic disease (MASLD). These health mediators should be considered along with individual SDOH in clinical care and healthcare quality and equity improvement, a large retrospective study of adults with MASLD at a multi-state healthcare institution concluded.

Across quartiles, patients in the most disadvantaged neighborhoods (according to home addresses) vs the least disadvantaged had worse outcomes and were also disproportionately Hispanic, Black, and Native American/Alaska Native, more often Spanish-speaking in primary language, and more often uninsured or on Medicaid, according to Karn Wijarnpreecha, MD, MPH, of the Division of Gastroenterology and Hepatology at University of Arizona College of Medicine–Phoenix, and colleagues writing in Clinical Gastroenterology and Hepatology.

Even after adjustment for measures in the Social Deprivation Index (SDI), the incidence of death, cirrhosis, diabetes mellitus (DM), and major adverse cardiovascular events (MACE) was higher in Native American/Alaska Native patients compared with their non-Hispanic White counterparts. The SDI is a composite measure of seven demographic characteristics from the American Community Survey, with scores ranging from 1 to 100 and weighted based on characteristics from national percentile rankings.

Aligning with the growing prevalence of obesity and DM, MASLD has increased substantially over the past three decades, and is now the leading cause of chronic liver disease in this country and the world. 

This rise in prevalence has underscored health disparities in MASLD and prompted research into linkd between liver disease and SDOH, defined as the conditions under which people are born, grow, live, work, and age. These are fundamental drivers of health disparities, including those in MASLD.
 

Study Details

Primary outcomes were MASLD burden, mortality, and comorbidities by neighborhood SDOH, assessed using the SDI in cross-sectional and longitudinal analyses.

A total of 69,191 adult patients (more than 50% female) diagnosed with MASLD were included, 45,003 of whom had at least 365 days of follow-up. They were treated from July 2012 to June 2023 in Banner Health Systems, a network that includes primary-, secondary-, and tertiary-care centers in Arizona, Colorado, Wyoming, Nevada, Nebraska, and California.

The median follow-up time was 48 months. Among patients across SDI quartiles (age range 49 to 62 years), 1390 patients (3.1%) died, 902 (2.0%) developed cirrhosis, 1087 (2.4%) developed LRE, 6537 (14.5%) developed DM, 2057 (4.6%) developed cancer, and 5409 (12.0%) developed MACE.

Those living in the most disadvantaged quartile of neighborhoods compared with the least had the following higher odds:

• cirrhosis, adjusted odds ratio [aOR], 1.42 (P < .001)
• any cardiovascular (CVD) disease, aOR, 1.20 (P < .001),
• coronary artery disease, aOR, 1.17 (P < .001)
• congestive heart failure, aOR, 1.43 (P < .001)
• cerebrovascular accident, aOR, 1.19 (P = .001)
• DM, aOR, 1.57 (P < .001)
• hypertension, aOR, 1.38 (P < .001).

They also had increased incidence of death (adjusted hazard ratio [aHR], 1.47; P < .001), LRE (aHR, 1.31; P = .012), DM (aHR, 1.47; P < .001), and MACE (aHR, 1.24; P < .001). 

The study expands upon previous SDOH-related research in liver disease and is the largest analysis of neighborhood-level SDOH in patients with MASLD to date. “Our findings are consistent with a recent study by Chen et al of over 15,900 patients with MASLD in Michigan that found neighborhood-level social disadvantage was associated with increased mortality and incident LREs and CVD,” Wijarnpreecha and colleagues wrote. 

“Beyond screening patients for individual-level SDOH, neighborhood-level determinants of health should also be considered, as they are important mediators between the environment and the individual,” they added, calling for studies to better understand the specific neighborhood SDOH that drive the disparate outcomes. In practice, integration of these measures into medical records might inform clinicians which patients would benefit from social services or help guide quality improvement projects and community partnerships.

Wijarnpreecha had no conflicts of interest to disclose. Several coauthors reported research support, consulting/advisory work, or stock ownership for various private-sector companies.
 

A head-to-head comparison of the JAK inhibitor drug tofacitinib and chimeric monoclonal antibody infliximab in the treatment of acute severe ulcerative colitis (ASUC) shows that, contrary to concerns, tofacitinib is not associated with worse postoperative complications and in fact may reduce the risk of the need for colectomy.

“Tofacitinib has shown efficacy in managing ASUC, but concerns about postoperative complications have limited its adoption,” reported the authors in research published in Clinical Gastroenterology and Hepatology.“This study shows that tofacitinib is safe and doesn’t impair wound healing or lead to more infections if the patient needs an urgent colectomy, which is unfortunately common in this population,” senior author Jeffrey A. Berinstein, MD, of the Division of Gastroenterology and Hepatology, Michigan Medicine, Ann Arbor, Michigan, told GI & Hepatology News. 

Recent treatment advances for UC have provided significant benefits in reducing the severity of symptoms; however, about a quarter of patients go on to experience flares, with fecal urgency, rectal bleeding, and severe abdominal pain of ASUC potentially requiring hospitalization.

The standard of care for those patients is rapid induction with intravenous (IV) corticosteroids; however, up to 30% of patients don’t respond to those interventions, and even with subsequent treatment of cyclosporine and infliximab helping to reduce the risk for an urgent colectomy, patients often don’t respond, and ultimately, up to a third of patients with ASUC end up having to receive a colectomy.

While JAK inhibitor therapies, including tofacitinib and upadacitinib, have recently emerged as potentially important treatment options in such cases, showing reductions in the risk for colectomy, concerns about the drugs’ downstream biologic effects have given many clinicians reservations about their use.

“Anecdotally, gastroenterologists and surgeons have expressed concern about JAK inhibitors leading to poor wound healing, as well as increasing both intraoperative and postoperative complications, despite limited data to support these claims,” the authors wrote.

To better understand those possible risks, first author Charlotte Larson, MD, of the Department of Internal Medicine, Michigan Medicine, and colleagues conducted a multicenter, retrospective, case-control study of 109 patients hospitalized with ASUC at two centers in the US and 14 in France.

Of the patients, 41 were treated with tofacitinib and 68 with infliximab prior to colectomy. 

Among patients treated with tofacitinib, five (12.2%) received infliximab and four (9.8%) received cyclosporine rescue immediately prior to receiving tofacitinib during the index admission. In the infliximab group, one (1.5%) received rescue cyclosporine.

In a univariate analysis, the tofacitinib-treated patients showed significantly lower overall rates of postoperative complications than infliximab-treated patients (31.7% vs 64.7%; odds ratio [OR], 0.33; P = .006).

The tofacitinib-treated group also had lower rates of serious postoperative complications (12% vs 28.9; OR, 0.20; P = .016).

After adjusting for multivariate factors including age, inflammatory burden, nutrition status, 90-day cumulative corticosteroid exposure and open surgery, there was a trend favoring tofacitinib but no statistically significant difference between the two treatments in terms of serious postoperative complications (P = .061). 

However, a significantly lower rate of overall postoperative complications with tofacitinib was observed after the adjustment (odds ratio, 0.38; P = .023).

Importantly, a subanalysis showed that the 63.4% of tofacitinib-treated patients receiving the standard FDA-approved induction dose of 10 mg twice daily did indeed have significantly lower rates than infliximab-treated patients in terms of serious postoperative complications (OR, .10; P = .031), as well as overall postoperative complications (OR, 0.23; P = .003), whereas neither of the outcomes were significantly improved among the 36.6% of patients who received the higher-intensity thrice-daily tofacitinib dose (P = .3 and P = .4, respectively).

Further complicating the matter, in a previous case-control study that the research team conducted, it was the off-label, 10 mg thrice-daily dose of tofacitinib that performed favorably and was associated with a significantly lower risk for colectomy than the twice-daily dose (hazard ratio 0.28; P = .018); the twice-daily dose was not protective.

Berinstein added that a hypothesis for the benefits overall, with either dose, is that tofacitinib’s anti-inflammatory properties are key.

“We believe that lowering inflammation as much as possible, with the colon less inflamed, could be providing the benefit in lowering complications rate in surgery,” he explained.

Regarding the dosing, “it’s a careful trade-off,” Berinstein added. “Obviously, we want to avoid the need for a colectomy in the first place, as it is a life-changing surgery, but we don’t want to increase the risk of infections.” 

In other findings, the tofacitinib group had no increased risk for postoperative venous thrombotic embolisms (VTEs), which is important as tofacitinib exposure has previously been associated with an increased risk for VTEs independent of other prothrombotic factors common to patients with ASUC, including decreased ambulation, active inflammation, corticosteroid use, and major colorectal surgery.

“This observed absence of an increased VTE risk may alleviate some of the hypothetical postoperative safety concern attributed to JAK inhibitor therapy in this high-risk population,” the authors wrote.

Overall, the results underscore that “providers should feel comfortable using this medication if they need it and if they think it’s most likely to help their patients avoid colectomy,” Berinstein said.

“They should not give pause over concerns of postoperative complications because we didn’t show that,” he said.

Commenting on the study, Joseph D. Feuerstein, MD, AGAF, of the Department of Medicine and Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, noted that, in general, in patients with ASUC who fail on IV steroids, “the main treatments are infliximab, cyclosporine, or a JAK inhibitor like tofacitinib or upadacitinib, [and] knowing that if someone needs surgery, the complication rates are similar and that pre-operative use is okay is reassuring.”

Regarding the protective effect observed with some circumstances, “I don’t put too much weight into that,” he noted. “[One] could speculate that it is somehow related to faster half-life of the drug, and it might not sit around as long,” he said.

Feuerstein added that “the study design being retrospective is a limitation, but this is the best data we have to date.”

Berinstein and Feuerstein had no disclosures to report.

A version of this article appeared on Medscape.com . 

A head-to-head comparison of the JAK inhibitor drug tofacitinib and chimeric monoclonal antibody infliximab in the treatment of acute severe ulcerative colitis (ASUC) shows that, contrary to concerns, tofacitinib is not associated with worse postoperative complications and in fact may reduce the risk of the need for colectomy.

“Tofacitinib has shown efficacy in managing ASUC, but concerns about postoperative complications have limited its adoption,” reported the authors in research published in Clinical Gastroenterology and Hepatology.“This study shows that tofacitinib is safe and doesn’t impair wound healing or lead to more infections if the patient needs an urgent colectomy, which is unfortunately common in this population,” senior author Jeffrey A. Berinstein, MD, of the Division of Gastroenterology and Hepatology, Michigan Medicine, Ann Arbor, Michigan, told GI & Hepatology News. 

Recent treatment advances for UC have provided significant benefits in reducing the severity of symptoms; however, about a quarter of patients go on to experience flares, with fecal urgency, rectal bleeding, and severe abdominal pain of ASUC potentially requiring hospitalization.

The standard of care for those patients is rapid induction with intravenous (IV) corticosteroids; however, up to 30% of patients don’t respond to those interventions, and even with subsequent treatment of cyclosporine and infliximab helping to reduce the risk for an urgent colectomy, patients often don’t respond, and ultimately, up to a third of patients with ASUC end up having to receive a colectomy.

While JAK inhibitor therapies, including tofacitinib and upadacitinib, have recently emerged as potentially important treatment options in such cases, showing reductions in the risk for colectomy, concerns about the drugs’ downstream biologic effects have given many clinicians reservations about their use.

“Anecdotally, gastroenterologists and surgeons have expressed concern about JAK inhibitors leading to poor wound healing, as well as increasing both intraoperative and postoperative complications, despite limited data to support these claims,” the authors wrote.

To better understand those possible risks, first author Charlotte Larson, MD, of the Department of Internal Medicine, Michigan Medicine, and colleagues conducted a multicenter, retrospective, case-control study of 109 patients hospitalized with ASUC at two centers in the US and 14 in France.

Of the patients, 41 were treated with tofacitinib and 68 with infliximab prior to colectomy. 

Among patients treated with tofacitinib, five (12.2%) received infliximab and four (9.8%) received cyclosporine rescue immediately prior to receiving tofacitinib during the index admission. In the infliximab group, one (1.5%) received rescue cyclosporine.

In a univariate analysis, the tofacitinib-treated patients showed significantly lower overall rates of postoperative complications than infliximab-treated patients (31.7% vs 64.7%; odds ratio [OR], 0.33; P = .006).

The tofacitinib-treated group also had lower rates of serious postoperative complications (12% vs 28.9; OR, 0.20; P = .016).

After adjusting for multivariate factors including age, inflammatory burden, nutrition status, 90-day cumulative corticosteroid exposure and open surgery, there was a trend favoring tofacitinib but no statistically significant difference between the two treatments in terms of serious postoperative complications (P = .061). 

However, a significantly lower rate of overall postoperative complications with tofacitinib was observed after the adjustment (odds ratio, 0.38; P = .023).

Importantly, a subanalysis showed that the 63.4% of tofacitinib-treated patients receiving the standard FDA-approved induction dose of 10 mg twice daily did indeed have significantly lower rates than infliximab-treated patients in terms of serious postoperative complications (OR, .10; P = .031), as well as overall postoperative complications (OR, 0.23; P = .003), whereas neither of the outcomes were significantly improved among the 36.6% of patients who received the higher-intensity thrice-daily tofacitinib dose (P = .3 and P = .4, respectively).

Further complicating the matter, in a previous case-control study that the research team conducted, it was the off-label, 10 mg thrice-daily dose of tofacitinib that performed favorably and was associated with a significantly lower risk for colectomy than the twice-daily dose (hazard ratio 0.28; P = .018); the twice-daily dose was not protective.

Berinstein added that a hypothesis for the benefits overall, with either dose, is that tofacitinib’s anti-inflammatory properties are key.

“We believe that lowering inflammation as much as possible, with the colon less inflamed, could be providing the benefit in lowering complications rate in surgery,” he explained.

Regarding the dosing, “it’s a careful trade-off,” Berinstein added. “Obviously, we want to avoid the need for a colectomy in the first place, as it is a life-changing surgery, but we don’t want to increase the risk of infections.” 

In other findings, the tofacitinib group had no increased risk for postoperative venous thrombotic embolisms (VTEs), which is important as tofacitinib exposure has previously been associated with an increased risk for VTEs independent of other prothrombotic factors common to patients with ASUC, including decreased ambulation, active inflammation, corticosteroid use, and major colorectal surgery.

“This observed absence of an increased VTE risk may alleviate some of the hypothetical postoperative safety concern attributed to JAK inhibitor therapy in this high-risk population,” the authors wrote.

Overall, the results underscore that “providers should feel comfortable using this medication if they need it and if they think it’s most likely to help their patients avoid colectomy,” Berinstein said.

“They should not give pause over concerns of postoperative complications because we didn’t show that,” he said.

Commenting on the study, Joseph D. Feuerstein, MD, AGAF, of the Department of Medicine and Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, noted that, in general, in patients with ASUC who fail on IV steroids, “the main treatments are infliximab, cyclosporine, or a JAK inhibitor like tofacitinib or upadacitinib, [and] knowing that if someone needs surgery, the complication rates are similar and that pre-operative use is okay is reassuring.”

Regarding the protective effect observed with some circumstances, “I don’t put too much weight into that,” he noted. “[One] could speculate that it is somehow related to faster half-life of the drug, and it might not sit around as long,” he said.

Feuerstein added that “the study design being retrospective is a limitation, but this is the best data we have to date.”

Berinstein and Feuerstein had no disclosures to report.

A version of this article appeared on Medscape.com . 

A head-to-head comparison of the JAK inhibitor drug tofacitinib and chimeric monoclonal antibody infliximab in the treatment of acute severe ulcerative colitis (ASUC) shows that, contrary to concerns, tofacitinib is not associated with worse postoperative complications and in fact may reduce the risk of the need for colectomy.

“Tofacitinib has shown efficacy in managing ASUC, but concerns about postoperative complications have limited its adoption,” reported the authors in research published in Clinical Gastroenterology and Hepatology.“This study shows that tofacitinib is safe and doesn’t impair wound healing or lead to more infections if the patient needs an urgent colectomy, which is unfortunately common in this population,” senior author Jeffrey A. Berinstein, MD, of the Division of Gastroenterology and Hepatology, Michigan Medicine, Ann Arbor, Michigan, told GI & Hepatology News. 

Recent treatment advances for UC have provided significant benefits in reducing the severity of symptoms; however, about a quarter of patients go on to experience flares, with fecal urgency, rectal bleeding, and severe abdominal pain of ASUC potentially requiring hospitalization.

The standard of care for those patients is rapid induction with intravenous (IV) corticosteroids; however, up to 30% of patients don’t respond to those interventions, and even with subsequent treatment of cyclosporine and infliximab helping to reduce the risk for an urgent colectomy, patients often don’t respond, and ultimately, up to a third of patients with ASUC end up having to receive a colectomy.

While JAK inhibitor therapies, including tofacitinib and upadacitinib, have recently emerged as potentially important treatment options in such cases, showing reductions in the risk for colectomy, concerns about the drugs’ downstream biologic effects have given many clinicians reservations about their use.

“Anecdotally, gastroenterologists and surgeons have expressed concern about JAK inhibitors leading to poor wound healing, as well as increasing both intraoperative and postoperative complications, despite limited data to support these claims,” the authors wrote.

To better understand those possible risks, first author Charlotte Larson, MD, of the Department of Internal Medicine, Michigan Medicine, and colleagues conducted a multicenter, retrospective, case-control study of 109 patients hospitalized with ASUC at two centers in the US and 14 in France.

Of the patients, 41 were treated with tofacitinib and 68 with infliximab prior to colectomy. 

Among patients treated with tofacitinib, five (12.2%) received infliximab and four (9.8%) received cyclosporine rescue immediately prior to receiving tofacitinib during the index admission. In the infliximab group, one (1.5%) received rescue cyclosporine.

In a univariate analysis, the tofacitinib-treated patients showed significantly lower overall rates of postoperative complications than infliximab-treated patients (31.7% vs 64.7%; odds ratio [OR], 0.33; P = .006).

The tofacitinib-treated group also had lower rates of serious postoperative complications (12% vs 28.9; OR, 0.20; P = .016).

After adjusting for multivariate factors including age, inflammatory burden, nutrition status, 90-day cumulative corticosteroid exposure and open surgery, there was a trend favoring tofacitinib but no statistically significant difference between the two treatments in terms of serious postoperative complications (P = .061). 

However, a significantly lower rate of overall postoperative complications with tofacitinib was observed after the adjustment (odds ratio, 0.38; P = .023).

Importantly, a subanalysis showed that the 63.4% of tofacitinib-treated patients receiving the standard FDA-approved induction dose of 10 mg twice daily did indeed have significantly lower rates than infliximab-treated patients in terms of serious postoperative complications (OR, .10; P = .031), as well as overall postoperative complications (OR, 0.23; P = .003), whereas neither of the outcomes were significantly improved among the 36.6% of patients who received the higher-intensity thrice-daily tofacitinib dose (P = .3 and P = .4, respectively).

Further complicating the matter, in a previous case-control study that the research team conducted, it was the off-label, 10 mg thrice-daily dose of tofacitinib that performed favorably and was associated with a significantly lower risk for colectomy than the twice-daily dose (hazard ratio 0.28; P = .018); the twice-daily dose was not protective.

Berinstein added that a hypothesis for the benefits overall, with either dose, is that tofacitinib’s anti-inflammatory properties are key.

“We believe that lowering inflammation as much as possible, with the colon less inflamed, could be providing the benefit in lowering complications rate in surgery,” he explained.

Regarding the dosing, “it’s a careful trade-off,” Berinstein added. “Obviously, we want to avoid the need for a colectomy in the first place, as it is a life-changing surgery, but we don’t want to increase the risk of infections.” 

In other findings, the tofacitinib group had no increased risk for postoperative venous thrombotic embolisms (VTEs), which is important as tofacitinib exposure has previously been associated with an increased risk for VTEs independent of other prothrombotic factors common to patients with ASUC, including decreased ambulation, active inflammation, corticosteroid use, and major colorectal surgery.

“This observed absence of an increased VTE risk may alleviate some of the hypothetical postoperative safety concern attributed to JAK inhibitor therapy in this high-risk population,” the authors wrote.

Overall, the results underscore that “providers should feel comfortable using this medication if they need it and if they think it’s most likely to help their patients avoid colectomy,” Berinstein said.

“They should not give pause over concerns of postoperative complications because we didn’t show that,” he said.

Commenting on the study, Joseph D. Feuerstein, MD, AGAF, of the Department of Medicine and Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, noted that, in general, in patients with ASUC who fail on IV steroids, “the main treatments are infliximab, cyclosporine, or a JAK inhibitor like tofacitinib or upadacitinib, [and] knowing that if someone needs surgery, the complication rates are similar and that pre-operative use is okay is reassuring.”

Regarding the protective effect observed with some circumstances, “I don’t put too much weight into that,” he noted. “[One] could speculate that it is somehow related to faster half-life of the drug, and it might not sit around as long,” he said.

Feuerstein added that “the study design being retrospective is a limitation, but this is the best data we have to date.”

Berinstein and Feuerstein had no disclosures to report.

A version of this article appeared on Medscape.com .