Diagnostic subtype in re-hospitalized patients with bipolar affective disorder

Objective To explore the feasibility of clinical apply and the clinical characteristics of bipolar disorder subtypes classified by DSM-Ⅳ. Methods Sixty-two readmission patients with bipolar affective disorder were re-diagnosed according to the CCMD-2-R criteria. The patients whose diagnoses were identical to primary diagnoses were classified into subtypes according to DSM-Ⅳ criteria, and the clinical characters of each subtype were analyzed and compared. Results The average onset age of bipolar Ⅱ [(21±4) years] was 7 years earlier than that of bipolar Ⅰ [(28±6) years]. There was 5-year longer course of bipolar Ⅱ than that of bipolar Ⅰ, with the median course of 11 and 6 years respectively. The average episode times of bipolar Ⅱ [ (6±2) times] were more than that of bipolar Ⅰ (4±1). The prevalence of psychosis in the first and second relatives of bipolar Ⅱ patients (41% and 32% respectively) were higher than that of bipolar Ⅰ (both 6%). The incidence of suicide was higher in bipolar Ⅱ (55%) than in bipolar Ⅰ (3%) whereas trouble-making behavior was higher in bipolar Ⅰ (48%) than in bipolar Ⅱ (9%). The treatment response rate of bipolar Ⅱ (64%) was lower than that of bipolar Ⅰ (94%). All above differences were significant (P0.01, or P0.05). Conclusions It is of significance for DSM-Ⅳ classification of bipolar affective disorders into bipolar Ⅰ and bipolar Ⅱ. It is suggested to use this subtype classification in China.