Bipolar pharmacotherapy and suicidal behavior Part 2. The impact of antidepressants.

UNLABELLED: Antidepressant-induced mania and cycle acceleration is a potential risk in bipolar patients. Another serious risk of antidepressants, that of increasing suicidal behavior, has been identified in some affectively ill populations. However, there is a dearth of knowledge about the effects of antidepressants on suicidal behavior specifically in bipolar patients.

METHODS: Retrospective chart review of 405 veterans with bipolar disorder followed for a mean of three years, with month by month systematic assessment of current pharmacotherapy and suicide completion, attempt or hospitalization for suicidality. Chi-squared comparison of (log) rates of suicidal events during mood stabilizer monotherapy, antidepressant monotherapy, and combination of mood stabilizer and antidepressant.

RESULTS: Suicidal behavior event rates (per 100 patient years) were greatest during treatment with antidepressant monotherapy (25.92), least during mood stabilizer monotherapy (3.48), and intermediate during mood stabilizer + antidepressant combination treatment (9.75). These differences were statistically significant.

LIMITATIONS: In a clinical setting, antidepressants may have been prescribed because patients were deemed at greater risk of suicidality.

CONCLUSIONS: During treatment with antidepressants (even when coupled with mood stabilizers), patients with bipolar disorder have significantly higher rates of non-lethal suicidal behavior compared to those on mood stabilizers without antidepressants, and thus require careful monitoring.