Bipolar versus unipolar psychotic outpatient depression

The relationship between bipolar and unipolar psychotic depression has not been well studied. Therefore, the aim of the present study was to compare bipolar with unipolar psychotic outpatient depression.

Seventy consecutive unipolar (n = 40) and bipolar (n = 30) psychotic depressed outpatients were interviewed with the Structured Clinical Interview for DSM-IV, the Montgomery Asberg Depression Rating Scale, the Global Assessment of Functioning Scale, and the Brief Psychiatric Rating Scale.

Of the variables studied (age, duration of illness, severity, recurrences, atypical features, chronicity, gender, comorbidity, hallucinations, delusions), none was significantly different between unipolar and bipolar psychotic patients.

Bipolar psychotic depression was similar to unipolar psychotic depression on variables reported in the literature to distinguish bipolar from unipolar disorder.

The findings might suggest, but do not necessarily imply, that psychotic depression might be a distinct clinical entity.

Single interviewer, nonblind cross-sectional assessment, outpatient sample, sample size.