Background. There have been few large-scale epidemiological studies which have examined the prevalence of bipolar disorder in Korea. The aims of this study is to assess the prevalence of bipolar I and II disorders in Korean population.
Method. A total of 6,510 adults completed face-to-face interviews (response rate 81.7%) through randomly chosen one-person-per-households from July 2006 to April 2007 (Korean Epidemiologic Catchment Area study Replication). Lifetime and one-year prevalence and correlates were evaluated with the Korean version of the Composite International Diagnostic Interview (K-CIDI). Those identified were compared with subjects without bipolar disorder, on rates of co-morbidity with anxiety and substance use disorders as well as demographic features and measures of disability and service utilization. Polychotomous logistic regression was used to study the relationship between the three samples and these dependent variables.
Results. The lifetime and 12-month prevalences for DSM-IV bipolar disorders were 0.64% and 0.34%, respectively. There was no gender difference. Compared with subjects without bipolar disorder, those with bipolar disorder were distinguished by more likelihood of unemployment; greater likelihood of being widowed, separated or divorced; higher rates of nicotine use disorder and anxiety disorder; greater disability as measured by EQ5D; increased rates of service utilization; and higher lifetime rates of suicide attempts.
Conclusions. The prevalecne rate of bipolar disorder assessed by K-CIDI in Korea is similar to other East Asian countries, but still lower than the Western countries. This large national survey highlights the marked functional impairment caused by bipolar disorder, even when compared with major depressive disorder.