A Case-Control Study of Antidepressants and Attempted Suicide During Early Phase Treatment of Major Depressive Episodes

Objective: To estimate the relative risk of suicide attempts in child and adult outpatients initiating antidepressants for major depressive episodes compared to those not treated with antidepressants.

Method: A nested matched case-control study was performed with Medicaid administrative data (January 1, 1999-December 31, 2000) of outpatients treated for a major depressive episode. Beneficiaries initiating treatment for a major depressive episode were selected, excluding those who had recently received inpatient psychiatric treatment or outpatient treatment of pregnancy, major depressive episodes, bipolar disorder, schizophrenia or other psychoses, mental retardation, dementia, or delirium or recent treatment with a mood stabilizer, antidepressant, or antipsychotic. The outcome was treatment for a suicide attempt during the first 120 days after starting treatment for a major depressive episode. Controls were matched to cases on age, sex, race/ethnicity, recent treatment of substance use disorder, severity and type of major depressive episode, and other factors. Separate analyses were performed for adults (aged 19 to 64 years) and children (aged 6 to 18 years).

Results: Among children, antidepressant treatment was associated with a significant increase in suicide attempts (odds ratio [OR] = 2.08, 95% confidence interval [CI] = 1.06 to 4.10; cases, N = 51; controls, N = 239; p = .03). Among adults, antidepressant treatment was not significantly related to risk of suicide attempts (OR = 0.85, 95% CI = 0.57 to 1.28; cases, N = 185; controls, N = 893; p = .44), although among adult males, antidepressants were associated with a significant protective effect (OR = 0.32, 95% CI = 0.12 to 0.83; cases, N = 57; controls, N = 268; p = .01).

Conclusions: In these outpatients initiating treatment for a major depressive episode, antidepressant treatment appears to be associated with an increased risk of treated suicide attempts in children and a decreased risk in adult males.