The prevalence of bipolar disorder in primary care patients with depression or other psychiatric complaints: a systematic review.

ABSTRACT

BACKGROUND: Bipolar disorder prevalence in primary care patients with depression or other psychiatric complaints has been measured in several studies but has not been systematically reviewed. OBJECTIVE: To systematically review studies measuring bipolar disorder prevalence in primary care patients with depression or other psychiatric complaints. METHODS: We conducted a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses method in January 2013. We searched 7 databases using a comprehensive list of search terms. Included articles had a sample size of 200 patients or more and assessed bipolar disorder using a structured clinical interview or bipolar screening questionnaire in adult primary care patients with a prior diagnosis of depression or had an alternate psychiatric complaint. RESULTS: Our search yielded 5595 unique records. Seven cross-sectional studies met our inclusion criteria. The percentage of primary care patients with bipolar disorder was measured in 4 studies of patients with depression, 1 study of patients with trauma exposure, 1 study of patients with any psychiatric complaint, and 1 study of patients with medically unexplained symptoms. The percentage of patients with bipolar disorder ranged from 3.4%-9% in studies using structured clinical interviews and from 20.9%-30.8% in studies using screening measures. CONCLUSIONS: Bipolar disorder likely occurs in 3%-9% of primary care patients with depression, a trauma exposure, medically unexplained symptoms, or a psychiatric complaint. Screening measures used for bipolar disorder detection overestimate the occurrence of bipolar disorder in primary care owing to false positives.