Prevalence of bipolar disorder in the general population: a Reappraisal Study of the Netherlands Mental Health Survey and Incidence Study

OBJECTIVE: The Netherlands Mental Health Survey and Incidence Study (NEMESIS) is a Dutch population study using a fully structured interview (Composite International Diagnostic Interview, CIDI), administered by trained interviewers. Based on all three assessments of NEMESIS, 2.4% of the respondents were identified with lifetime bipolar disorder (DSM-III-R). The primary aim of the study was to estimate the prevalence of bipolar disorder in the same population based on a semistructured interview administered by clinicians. METHOD: Seventy-four persons identified with a lifetime CIDI/DSM-III-R bipolar disorder and 40 persons with a major depressive disorder (MDD) were reinterviewed with the Structured Clinical Interview for DSM (SCID). RESULTS: Based on the SCID, 30 of 74 respondents with a CIDI/DSM-III-R bipolar disorder and eight of 40 respondents with MDD met DSM-IV criteria for bipolar disorder or cyclothymia, corresponding with an adjusted lifetime prevalence in these groups of 1% (95% CI: 0.7-1.3%) and 4.2% (95% CI: 1.6-6.9%) respectively. CONCLUSION: Compared with the SCID, the CIDI on the one hand overdiagnoses bipolar disorder but on the other hand underdiagnoses bipolar disorder.