Objective: Unipolar and bipolar depression (UD and BD) differ strikingly in respect to neurobiology, course and management, but their apparent clinical similarity often leads to misdiagnosis resulting in chronicity of course and treatment failure. In this study we have tried to assess whether UD and BD can be differentiated on the basis of their dissociative symptoms.
Methods: Thrty-six UD patients and 35 BD patients in active episodes, without any psychiatric comorbidity were selected from outpatient department and compared for depressive and dissociative symptoms using Hamilton Depression Rating Scale and Dissociative Experience Scale-II (DES-II).
Results: We found that thought the two groups didn't differ in terms of the socio-demographic or clinical variables, BD group had significantly higher dissociative experience (U=343, p=0.001) than UD and the difference remained significant even after adjusting for the confounding factors.
Conclusion: Our study shows that dissociative symptoms are significantly more prevalent in the depressive episodes of bipolar affective disorder as compared to the UD and can be an important tool in differentiating between the two disorders with very similar clinical profile. The difference can be measured using a simple self-report questionnaire like DES-II.
Keywords: Bipolar depression.; Bipolar disorder; Dissociative disorders.