Prevalence of bipolar spectrum disorders in migraine patients

Abstract

Comorbidity of migraine and mood disorders has long been recognized. Most of the studies have focused on the relationship between migraine and major depression with only few studies suggesting a special association between migraine and bipolar spectrum disorders. We aimed to evaluate the prevalence of bipolar disorder in migraine patients in a specialized headache outpatient clinic. The sample consisted of 78 consecutive patients with migraine headache presenting to the specialized headache outpatient clinic in a Medical Faculty. Migraine diagnosis was established with the International Headache Society's criteria for migraine. Patients were evaluated with Structured Clinical Interview for DSM-IV for mood disorders. Bipolar spectrum definition was broadened with the presence of Akiskal's criteria for affective temperaments (cyclothymic, hyperthymic, irritable, and depressive). Patients in the bipolar spectrum comprised 10.3% (n=8) of the sample. 11 patients (14.1%) had a diagnosis of unipolar depression and 7 patients (9%) had a diagnosis of dysthymic disorder. 41% of the patients (n=32) had an affective temperament. Bipolar disorder was observed with increased frequency in this migraine sufferer population, supporting previous findings of increased prevalence of bipolar disorders in patients with migraine. Increased frequency of affective temperaments might be considered in the context of a common pathophysiological background for migraine and bipolar disorders where these temperaments are sub-threshold presentations of mood disorders. Therefore, the definition of patients with comorbid migraine and bipolar disorder may serve as a more homogenic subgroup of mood disorders for further studies.