TREATMENT OF DEPRESSION IN BIPOLAR DISORDER - NEW DIRECTIONS FOR RESEARCH

The objective of the study was to review the clinical literature on th e acute, somatic treatment of the depressed phase of bipolar disorder. We reviewed all available published studies of ''standard'' somatic t reatments (lithium, antidepressant and anticonvulsant agents, and elec troconvulsive therapy [ECT]) reporting three or more depressed bipolar patients who were not psychotic, rapid cycling, or previously treatme nt refractory. We also reviewed all studies of ''nonstandard'' pharmac ologic treatments involving even a single case of a depressed bipolar patient. Data sources included the MEDLINE database and relevant refer ences from articles obtained in this search and in major reviews. Five of seven studies comparing ECT with antidepressant agents find ECT mo re efficacious. Eight of nine controlled comparisons find lithium supe rior to placebo in depressed bipolar patients. Three controlled compar isons of lithium to tricyclic antidepressants suggest that lithium is equivalent to tricyclic drugs in such patients. Three double-blind, co ntrolled studies indicate that carbamazepine is more effective than pl acebo. Limited data on other antidepressant classes suggest that monoa mine oxidase inhibitors, bupropion, and serotonergic agents may offer some advantages over tricyclic antidepressants in this population. Som e ''nonstandard'' treatments also show some potential in bipolar patie nts. The possibility of switching into a manic episode is an important consideration with many of the agents studied, although little remain s known about spontaneous versus treatment-associated mood shifts. In contrast to the extensive literature on the acute treatment of the man ic phase of bipolar disorder and on the prophylaxis of manic and depre ssive episodes, there are few studies of treatment of the depressed ph ase of bipolar disorder, and their results generally are limited or in conclusive. Lithium generated a revolution in psychiatric treatment, b ut the treatment of the depressed phase of bipolar disorder remains a relatively neglected corner of the field. Several study designs may he lp to augment knowledge in the treatment of bipolar depression.