Antidepressants and suicidal behaviour in unipolar depression

Objective: To compare the rates of suicidal behaviour during vs. after discontinuation of treatment with antidepressants, and to determine the comparative rates of suicidal behaviour for patients maintained on tricyclic (TCA) vs. selective serotonin reuptake inhibitor (SSRI) antidepressants. Method: Charts were reviewed for 521 patients with major depressive disorder and/or dysthymic disorder. Periods of active treatment or discontinuation with SSRIs or TCAs were determined. Rates of completed suicide, suicide attempts, and hospitalization for suicidality were analyzed. Results: There was greater than a five-fold increase in risk for suicidal behaviour after discontinuation of antidepressant treatment (P < 0.0001). The rates of suicidal behavior during treatment with SSRIs or TCAs were similar. Conclusion: Suicidal behaviour in unipolar depressed patients treated with antidepressants increases substantially after medication discontinuation. This effect occurred in both patients who were maintained on SSRIs and TCAs. The findings support a possible protective effect on suicidal behaviour for both SSRIs and TCAs.