Isotretinoin use and risk of depression, psychotic symptoms, suicide, and attempted suicide

Background: It has been suggested that there is a causal association betwee n isotretinoin therapy and the risk of depression, psychotic symptoms, suic ide, and attempted suicide. Objective: To further investigate the proposed association between isotreti noin therapy and the risk of depression, psychotic symptoms, suicide, and a ttempted suicide using a formal study design. Design: Large population-based cohort studies. Setting: The Canadian Saskatchewan Health Database and the United Kingdom G eneral Practice Research Database. Patients: Data were analyzed for 7195 isotretinoin users and 13 700 oral an tibiotic users with acne from the Canadian Saskatchewan Health Database and for 340 isotretinoin users and 676 oral antibiotic users with acne from th e United Kingdom General Practice Research Database. All subjects had compu ter-recorded histories of between 6 months and 5 years before, and at least 12 months after, their first isotretinoin or antibiotic prescription. Outcome Measure: Prevalence rates of neurotic and psychotic disorders, suic ide, and attempted suicide were compared between isotretinoin and antibioti c users and within isotretinoin users as their own comparison (pretreatment vs posttreatment). The results were expressed as relative risks, calculate d using multiple logistic regression analyses. Results: Relative risk estimates, comparing isotretinoin use and oral antib iotic use with nonexposure to either drug for newly diagnosed depression or psychosis, were approximately 1.0 regardless of the data source. Similarly , relative risk estimates were all around 1.0 when comparing before with af ter isotretinoin use. The relative risk estimate for suicide and attempted suicide was 0.9 (95% confidence interval, 0.3-2.4) when comparing current i sotretinoin exposure with nonexposure. Conclusion: This study provides no evidence that use of isotretinoin is ass ociated with an increased risk for depression, suicide, or other psychiatri c disorders.