A COMPARISON OF COMORBID PATTERNS IN TREATMENT-RESISTANT UNIPOLAR ANDBIPOLAR DEPRESSION

Objective: To examine the occurrence of concomitant psychiatric disord ers in patients with treatment-resistant unipolar and bipolar depressi on. Method: Forty-nine patients participated as subjects. Twenty-four (49%) had unipolar depression and 25 (51%) had bipolar depression usin g DSM-III-R criteria. Structured clinical interviews were conducted wi th all patients. Chart reviews and interviews with family members were also carried out Information relating to both current and lifetime di agnoses was obtained. Results: Of the entire sample, 75.5% were found to have at least one other Axis I diagnosis and 46.9% had at least two additional Axis I diagnoses. The unipolar group had significantly mor e current comorbid diagnoses. When type of diagnoses was examined, uni polar patients had significantly more anxiety diagnoses at the time of the index episode, and over their entire lifetime. Bipolar patients h ad significantly more lifetime substance abuse diagnoses. Conclusions: Axis I comorbidity appears to be differentially associated with treat ment resistance in unipolar and bipolar depression.