Prevalence and predictors of bipolar disorders in patients with a major depressive episode: The Japanese epidemiological trial with latest measure of bipolar disorder (JET-LMBP)

AbstractBackgroundFor patients with a major depressive episode, early differential diagnosis of bipolar disorder and subsequent appropriate treatment are critical. This study, conducted in clinical settings in Japan, examined patients with a major depressive episode to investigate the prevalence and predictors of bipolar disorders.MethodsA total of 448 patients with a major depressive episode were interviewed using the Mini-International Neuropsychiatric Interview to determine the presence of mood episodes and psychiatric comorbidities. The diagnosis of bipolar disorder was based on the collected information according to the DSM-IV-TR.ResultsOf the 448 patients with a major depressive episode, 114 patients (25.4%) were diagnosed with bipolar disorder. Multivariate logistic regression identified five predictors that were significantly correlated with bipolar disorder: antidepressant-related switch to mania/hypomania, mixed depression, two or more previous mood episodes within the past year, early age at the onset of a major depressive episode (