目標：探討台灣南部地區重鬱症與雙極症之人口學特徵與症狀分佈情形，及社交關係的家族聚集現象。方法：透過家族研究設計收取290位個案(127位雙極症第一型，43.8%；84位雙極症第二型，29.0%；79位重鬱症患者，27.2%)及399位家屬。透過組合性國際診斷會談問卷(CIDI)收集人口學變項及臨床表徵資料。重鬱症與雙鬱症患者在社交關係的家族聚集由混和模式(mixed models)、組內相關係數(intraclass correlation coefficient)評估。結果：重鬱症中女性為男性兩倍，雙極症中男比女約一比一。重鬱症患者結婚率較雙極症高。兩種患者中九成社經地位較低。雙極症的發病年齡較重鬱症早且發作次數頻繁。兩種患者的功能損傷越嚴重則越少與朋友聯絡，且對於親屬與朋友的社交依賴存在家族聚集現象。結論：重鬱症與雙極症存在不同的臨床特性且在社交關係有家族聚集現象。

Objectives: To investigate the demographic features and the distribution of symptoms for major depressive disorder (MDD), bipolar disorder type I (BPI), and bipolar disorder type II (BPII) families in Southern Taiwan, and to evaluate the familial aggregation of social relationships for the three diagnoses. Methods: A total of 290 probands (127, 43.8% BPI; 84, 29.0% BPII; and 79, 27.2% MDD) and 399 relatives participated in this study. Participants were interviewed by well-trained interviewers using the Composite International Diagnostic Interview (CIDI) in order to collect data about diagnosis, demographic and clinical features. Familial aggregation of social relationships were evaluated by the use of mixed models and intraclass correlation coefficients. Results: The female to male ratio was two to one in MDD and one to one in BPD. A higher proportion of MDD patients were married than were BPD patients. About ninety percent of all mood disorder patients had low socioeconomic status. Patients with BPD had an earlier age of onset and more depressive/manic episodes than did MDD patients. Probands with more severe impairments tended to have fewer contacts with friends. A familial aggregation of social dependence was observed in our sample. Conclusions: MDD and BPD patients have different clinical characteristics and familial aggregation of social relationships.