Objective: To report on the prevalence of comorbid migraine in bipolar disorder and the implications for bipolar age of onset, psychiatric comorbidity, illness course, functional outcome, and medical service utilization.
Background: Migraine comorbidity is differentially reported in bipolar versus unipolar depressed clinical samples. The bipolar disorder-migraine association and its consequences have been infrequently reported in epidemiological studies.
Methods: Data for this analysis were derived from respondents (n = 36 984) to the Canadian Community Health Survey - Mental Health and Well-Being (CCHS). Respondents reporting a lifetime WHO-CIDI-defined manic episode and physician-diagnosed migraine (lifetime) were compared to respondents without migraine on sociodemography, course of illness, and medical service utilization indices.
Results: An estimated 2.4% of the sample met criteria for bipolar disorder. Persons with bipolar disorder had a relatively higher prevalence of migraine versus the general population (24.8% vs. 10.3%; P < .05). The sex-specific prevalence of comorbid migraine in bipolar disorder was 14.9% for males and 34.7% for females. Bipolar males with comorbid migraine were more likely to live in a low income household (P < .05); receive welfare and social assistance (P < .05); report an earlier age of onset of bipolar disorder (P < .05); and have a higher lifetime prevalence of comorbid anxiety disorders (P < .05). Bipolar males with comorbid migraine were also more likely to utilize primary (P < .05) and mental health care services (P < .05) . Bipolar females with comorbid migraine had more comorbid medical disorders (P < .05) and were more likely to require help with personal or instrumental activities of daily living when compared to bipolar females without migraine.
Conclusion: Bipolar disorder with comorbid migraine is prevalent and associated with greater dysfunction and medical service utilization, notable in males. Opportunistic screening and surveillance for bipolar and comorbid migraine is warranted.