치료저항성 우울증 환자의 양극성 경향

The Bipolar Diathesis in Patients with Treatment Resistant Depression

  Objective : In this study, we determined the prevalence of bipolarity in patients with treatment resistant depression (TRD) by investigating demographic and clinical characteristics, diagnostic subtypes, and illness outcome. Method : A medical record review of patients admitted to a university hospital with the diagnosis of major depressive disorder (MDD) was conducted. DSM-Ⅳ diagnoses at index hospitalization and six months after discharge and detailed clinical information were obtained. We categorized subjects into a TRD group or a non-TRD group and re-evaluated the patients using the recently proposed criteria for bipolar spectrum disorder (BSD). Patients in the TRD group were compared with patients in the non-TRD group with regard to the prevalence rate of BSD at the index hospitalization and at the end of the follow up period. Results : There were 281 patients diagnosed as MDD. At discharge, the number of patients who fulfilled the criteria for BSD was higher (p＜.001) in the TRD group (32/68, 47.1%) than in the non-TRD group (8/213, 3.8%). At the end of six-month follow-up period, the diagnoses of 38 patients changed ; 18 (26.5%) in the TRD group were subsequently classified as having bipolar disorder, and seven (3.3%) in the non-TRD group (p＜0.001). There was no difference between these two groups in other clinical and demographic variables. Conclusion : The findings suggest that a large number of patients with TRD have a bipolar diathesis.