Early life exposure to antibiotics and the risk of mood and anxiety disorders in children and adolescents: A population-based cohort study

Objective: Mood and anxiety disorders (MADs) are common conditions with multiple aetiologies. Exposure to antibiotics has been proposed as a possible risk factor in animal studies. We aimed to assess maternal antibiotic use in pregnancy and child antibiotic use in the first three years of life, collectively called early life, as potential risk factors for subsequent development of MADs during childhood and adolescence. Methods: A population-based retrospective cohort study was conducted including 221,139 children born in Manitoba, Canada between 1996 and 2012. Exposure was defined as having filled one or more antibiotic prescriptions during early life. Children were followed until the earliest MADs diagnoses, 19th birthday, migration, death, or end of the study period. We computed crude and adjusted hazard ratios (aHRs) with corresponding 95% confidence intervals (CIs) using Cox proportional hazard regression. Results: Children born to mothers who received one or more antibiotic courses in pregnancy had significantly higher rates of MADs compared with non-exposed children (aHR 1.08, 95% CI 1.03,1.13). Overall antibiotic exposure during the first three years of life was not significantly associated with MADs (aHR 1.00, 95% CI 0.94,1.07). A significantly increased risk of MADs was observed after postnatal exposure to tetracyclines, aminoglycosides, quinolones (33%) or sulfonamides and trimethoprim (28%). Postnatal exposure to macrolides, lincosamides, and streptogramins significantly reduced the risk of MADs by 16%. Conclusion: Early life exposure to antibiotics is associated with different risk effects on MADs in children. The apparent associations may have been confounded by indication and may not be clinically meaningful.

Automated summary

This study on 221,139 children born in Manitoba, Canada between 1996 and 2012 found that maternal antibiotic use in pregnancy was significantly associated with an increased risk of mood and anxiety disorders (MADs) in children. However, overall antibiotic exposure in the first three years of life and specific postnatal antibiotic exposures showed varying effects on the risk of MADs, with some even having a protective effect. The associations observed may have been confounded by indication and may not have clinical significance.