Importance: Isotretinoin is hypothesized to contribute to the development of psychiatric disorders, but the epidemiological association and risk factors associated with psychiatric disorders among isotretinoin users remain unclear.
Objective: To clarify the absolute and relative risk and risk factors associated with suicide and psychiatric disorders among isotretinoin users.
Data sources: PubMed, Embase, Web of Science, and Scopus were searched from inception until January 24, 2023.
Study selection: Randomized trials and observational studies were selected if they reported the absolute risk, relative risk, and risk factors for suicide and psychiatric disorders among isotretinoin users.
Data extraction and synthesis: Relevant data were extracted and risk of bias was evaluated at the study level using the Newcastle-Ottawa Scale. Data were pooled using inverse variance-weighted meta-analyses. Heterogeneity was measured using the I2 statistic, and meta-regression analyses were performed.
Main outcomes and measures: Absolute risk (percentage), relative risks (risk ratios [RR]), and risk factors (RR) of suicide and psychiatric disorders among isotretinoin users.
Results: A total of 25 studies including 1 625 891 participants were included in the review and 24 in the meta-analysis. Among the included studies, participants' average age ranged from 16 to 38 years, and distribution by sex ranged from 0% to 100% male. The 1-year pooled absolute risk from between 2 and 8 studies of completed suicide, suicide attempt, suicide ideation, and self-harm were each less than 0.5%, while that of depression was 3.83% (95% CI, 2.45-5.93; I2 = 77%) in 11 studies. Isotretinoin users were less likely than nonusers to attempt suicide at 2 years (RR, 0.92; 95% CI, 0.84-1.00; I2 = 0%), 3 years (RR, 0.86; 95% CI, 0.77-0.95; I2 = 0%), and 4 years (RR, 0.85; 95% CI, 0.72-1.00; I2 = 23%) following treatment. Isotretinoin was not associated with the risk of all psychiatric disorders (RR, 1.08; 95% CI, 0.99-1.19; I2 = 0%). Study-level meta-regression found that studies with participants of older age reported lower 1-year absolute risk of depression, while those with a higher percentage of male participants reported a higher 1-year absolute risk of completed suicide.
Conclusions and relevance: The findings suggest that at a population level, isotretinoin users do not have increased risk of suicide or psychiatric conditions but may instead have a lower risk of suicide attempts at 2 to 4 years following treatment. While these findings are reassuring, clinicians should continue to practice holistic psychodermatologic care and monitor patients for signs of mental distress during isotretinoin treatment.