according to a population-based study of surgery patients.
, of the department of surgery at the University of Michigan, Ann Arbor, and his coauthors analyzed data from the Michigan Surgical Quality Collaborative and sampled 2,392 patients who underwent 1 of 12 common surgical procedures in Michigan between Jan. 1 and Sept. 30, 2017, and were prescribed opioids for pain. For all patients, the quantity of opioid prescribed – converted to oral morphine equivalents (OMEs) to adjust for varying potency – was considerably greater than the quantity actually consumed by the patient, wrote Dr. Howard and his colleagues in .
The study findings have troubling implications, the authors suggested. “Overprescribing was universally observed in this cohort, affecting each of the 12 procedures analyzed. This phenomenon was not limited to single, outlier institutions, but was widespread across many hospitals. This resulted in increased opioid consumption among patients who received larger prescriptions, as well as tens of thousands of leftover pills in 9 months that entered communities across the state of Michigan.”
The median amount prescribed was 150 OMEs, the equivalent of 30 pills of hydrocodone/acetaminophen, 5/325 mg. The median consumed, as reported by patients, was 45 OMEs, or 9 pills, meaning only 27% of the prescribed amount was used. Prescription size was also strongly associated with higher consumption; patients used an additional 0.53 OMEs (95% confidence interval, 0.40-0.65; P less than .001), or 5.3 more pills, for every 10 extra pills prescribed. The larger the initial prescription, the more patients used, an association that persisted when the data were adjusted for procedure and patient-specific factors such as postoperative pain.
The study’s acknowledged limitations included an inability to estimate how many patients were contacted for patient-reported outcome collection, which obscures how representative this sample may be of the patient population in general. There was also no data gathered regarding preoperative opioid use, a near certainty in this cohort given a 3%-4% prevalence of chronic opioid use.
That said, the investigators noted that “intentionally keeping future recommendations liberal in quantity may ultimately aid with widespread adoption, especially for clinicians concerned that prescribing reductions may lead to increased pain and calls for refills after surgery.” They commended local efforts already underway to combat this issue– including their own work at the University of Michigan, where evidence-based prescribing recommendations resulted in a 63% reduction in opioid prescription size without an increase in refills or pain – but reiterated that more needs to be done at a state level.
The authors offered a possible reason for the link between prescription size and patient consumption. “A plausible explanation for the association between prescription size and medication use is the anchoring and adjustment heuristic. This is a psychologic heuristic wherein a piece of information serves as an anchor on which adjustments are made to reach an estimation or decision. For example, obesity literature has shown that food intake increases with portion size. In this case, a larger amount of opioids may serve as a mental anchor by which patients estimate their analgesic needs.”
Michael Englesbe, MD, Jennifer Waljee,MD, and Chad Brummett, MD, reported receiving funding from the Michigan Department of Health and Human Services and the National Institute on Drug Abuse. Joceline Vu, MD, reported receiving funding from the National Institutes of Health Ruth L. Kirschstein National Research Service Award; Jay Lee, MD, reported receiving funding from the National Cancer Institute.
SOURCE: Howard R et al. JAMA Surg. 2018 Nov 7.