Repeated exposure to antibiotics in infancy is associated with early childhood obesity, according to a study published in the November 2014 issue of JAMA Pediatrics.
The cohort study was conducted in a network of primary care practices affiliated with the Children’s Hospital of Philadelphia. Antibiotic treatment episodes and obesity outcomes were analyzed in 64,580 children up to 23 months of age.
The results of the study indicated that cumulative exposure to antibiotics (≥4 episodes) was associated with later obesity (relative risk [RR]: 1.11), with a stronger association seen for broad-spectrum antibiotics (RR: 1.16). Early exposure to broadspectrum antibiotics was also associated with obesity (RR: 1.11, at 0 to 5 months of age; RR: 1.09, at 6 to 11 months of age). On the other hand, narrow-spectrum antibiotics were not associated with obesity at any age or frequency of treatment. This association persisted after accounting for known risk factors, such as sex, urban primary care practice, insurance type, diagnosis of asthma, and steroid use.
The authors acknowledged that additional investigations were necessary to better study the relationship between confounding geographic, social, and clinical factors and the incidence of childhood obesity. Based on the study results, however, the authors concluded that the use of broad-spectrum antibiotics before 24 months of age may be a risk factor for obesity.
The authors noted that the study “provides additional support for the adoption of treatment guidelines for common pediatric conditions that emphasize limiting antibiotic use to cases where efficacy is well-demonstrated.”