Relationship between antibiotic exposure and subsequent mental health disorders in a primary care health system

Objective: To evaluate the relationship between antibiotic exposure and subsequent psychiatric disorders in a Pediatric primary care setting. Study design: We conducted a retrospective cohort study using electronic clinical record data for patients ages 8–20 years seen in the outpatient setting of a large urban primary health care practice from 1/1/13 to 12/1/2018. We employed adjusted Cox regression analyses to study the relationship between prescriptions for anti-infective agents and subsequent diagnosis of anxiety or depression. Results: Prescription of anti-infective medication was associated with a hazard rate ratio (HRR) of 1.21 (95%-CI ​= ​1.00–1.45). A first prescription for a broad-spectrum antibiotic (compared to those with no prescription, narrow-spectrum prescription, or topical prescription) was associated with an HRR of 1.27 (95%-CI ​= ​1.04–1.54). The number of anti-infectives prescribed over the course of the study period was associated with an HRR of 1.05 (95%-CI ​= ​1.00–1.10). There was no significant relationship between prescription of topical or narrow-spectrum antibiotics, antifungal, or antiviral medication and subsequent diagnosis of anxiety or depression. Stratified analysis revealed that the association between anti-infective prescription and anxiety and depression was driven by males, among whom prescription of any antibiotic was associated with an HRR of 1.45 (95%-CI ​= ​1.05–1.99). Conclusions: Infections treated with broad-spectrum antibiotics were associated with increased risks of anxiety and/or depression, especially in males. Exploration of the relationship between antibiotic exposure and subsequent mental health disorders is warranted along with continued vigilance in antibiotic prescribing practices in children.