Bipolar depression: an underestimated treatment challenge

We sought to determine whether depressive and mixed/cycling episodes were as responsive to standardized pharmacotherapeutic interventions as were manic episodes in bipolar 1 patients. As part of the Maintenance Therapies in Bipolar Disorder (MH29618, E. Frank, PI) study, forty-two acutely ill bipolar 1 patients who had been randomly assigned to one of two preliminary phase non-pharmacologic treatment strategies (interpersonal and social rhythm therapy [IPSRT] or a standard medication clinic approach) were treated according to a standardized pharmacotherapeutic protocol. Symptom severity was measured weekly with the Hamilton Depression Rating Scale and the Bech-Rafaelsen Mania Scale in order to assess symptomatic remission. Survival analysis with the proportional hazards model was performed on time to remission. Manic patients were significantly more likely to achieve clinical remission than the depressed patients (100 vs. 59%) and did so significantly more rapidly. The difference in proportion remitting and time to remission between the depressed and mixed/cycling groups was not statistically significant. No significant effect for non-pharmacologic treatment assignment was found. These results point to the need to develop more effective treatments for bipolar depression. They also suggest that psychotherapy has a limited impact in the acute phase treatment of bipolar episodes.