Children receiving broad-spectrum antibiotics before age 2 years are at a slightly higher risk for obesity in early childhood, according to a recent study.
Children exposed to any antibiotics at least four times before turning 2 years old were 11% more likely to be obese between ages 2 and 5 years, even after accounting for other risk factors, compared with children receiving no antibiotics, reported Dr. L. Charles Bailey of Children’s Hospital of Philadelphia, and his associates.
But this association was driven primarily by broad-spectrum antibiotics, which increased the risk of obesity 16% in children who took them at least four times before 24 months old. No association with obesity was seen for narrow-spectrum antibiotics, which included penicillin and amoxicillin.
“If validated in other studies, this observation suggests a potentially modifiable risk factor for childhood obesity, given the relatively high use of broad-spectrum drugs, although interventions in this area have proven difficult in practice, Dr. Bailey’s team reported.
Dr. Bailey and his associates analyzed data from the medical records of 65,480 children who had at least three primary care visits between 2001 and 2009: one before 11 months old, one between 12 and 23 months, and one between 24 and 59 months as long as height and weight had been taken to calculate body mass index (BMI). The researchers defined obesity as 95th percentile or higher on the 2000 National Health and Nutrition Examination Survey growth norms.
Antibiotics were the most commonly prescribed medication to young children – provided an average 2.3 times each to 69% of the children before 24 months old – followed by oral steroids and antireflux medications.
Children exposed to just one round of broad-spectrum antibiotics between 0 and 5 months old had an 11% higher risk of obesity by age 5 years, compared with those receiving no antibiotics. Only 14% of children received antibiotics before 6 months old.
Children also were more likely to be obese if they had received steroids, were male, were Hispanic, had public insurance, went to an urban practice, or had been diagnosed with asthma or wheezing. But the researchers found no association between child obesity and antireflux medications or with pharyngitis, otitis media, or any other common infections.
The study was supported by the American Beverage Foundation for a Healthy America. The authors had no disclosures.