The Clinical Features of Bipolar Depression: A Comparison With Matched Major Depressive Disorder Patients

Background: Despite a resurgence of interest inthe treatment of bipolar depression, there have been fewcontrolled studies of the clinical characteristics of thiscondition. Identification of any distinctive clinical”signatures” of bipolar depression would be helpful indetermining treatment options in the clinical setting.

Method: From a cohort of 270 inpatients andoutpatients assessed in detail during a DSM-IV major depressiveepisode, 39 bipolar I disorder patients were identified andclosely matched with 39 major depressive disorder patients forgender, age, and the presence or absence of DSM-IV melancholicsubtype. Patients were compared on a broad range of parametersincluding the Hamilton Rating Scale for Depression (depressionseverity), 54 depressive symptoms, the Newcastle EndogenousDepression Diagnostic Index, 3 family history items, 2 physicalhealth items, the CORE scale (psychomotor disturbance), and 5history items.

Results: Although the bipolar patients were nomore severely depressed than the major depressive disordercontrols, they were more likely to demonstratepsychomotor-retarded melancholic and atypical depressive featuresand to have had previous episodes of psychotic depression. Thesefindings were largely duplicated even when the population wasconfined to those with DSM-IV melancholia.

Conclusion: The clinical admixture ofpsychomotor-retarded melancholic signs and symptoms,”atypical” features, and (less frequently) psychosismay provide a “bipolar signature” in clinical scenarioswhen there is uncertainty concerning the polarity of a depressivepresentation.