Abstract
Objective: Major mental disorders including bipolar disorder aggregate in families. There are also non-familial, solitary cases and familial and non-familial cases may differ. Most of the studies regarding familiality in bipolar disorder targeted similar and dissimilar characteristics of the disease within families. There is a lack of studies targeting between subject differences in patients from different families. The aim of this study is to assess and compare clinical characteristics of type I bipolar patients with and without a family history of bipolar disorders.

Method: This study was conducted on outpatients of Raşit Tahsin Mood Disorders Centre of Bakırköy Research and Training Hospital. The medical records of 112 participants (69 female, 43 male, mean age: 41.54±11.19, range: 22-75, 64 of which had family history and 48 without family history) with type I Bipolar Disorder were collected. Missing information was obtained by phone interviews from both patients and first degree relatives. Information of the patients without a family history of any psychiatric disorder was checked with a senior family member.

Results: Postpartum episode rates, comorbid psychiatric disorders, number of subjects ever had past mixed episodes, and nicotine dependency rates were found to be significantly higher in patients with family history. No significant difference was detected between groups in terms of age, gender, education, age at disease onset, number of episodes, and number of hospitalizations.

Conclusions: Comorbidity, postpartum episodes, lifetime mixed episodes, and smoking were found to be higher in patients with family history and thus associated with bipolarity. Postpartum episodes and comorbidities can be expected to be more prevalent in patients with family history. However clinical characteristics should be further investigated in larger samples.

Key words: Familial, non-familial, bipolar disorder