Migraine and risk of ischaemic stroke: a case-control study.

Abstract

To determine whether migraine is a risk factor for ischaemic stroke. A case-control study. Two hospitals in Paris. 212 patients with stroke (137 men and 75 women) and 212 controls matched for sex, age (to within five years), and history of hypertension. Ischaemic stroke, confirmed by brain computed tomography or magnetic resonance imaging, and history of headache, recorded with structured questionnaire during interview. Prevalence of migraine did not differ between patients with stroke and controls: 18/137 v 17/137 for men (odds ratio 1.1 (95% confidence interval 0.5 to 2.2), p = 0.86); 23/75 v 17/75 for women (odds ratio 1.6 (0.7 to 3.5), p = 0.24); and 41/212 v 34/212 for both sexes (odds ratio 1.3 (0.8 to 2.3), p = 0.33). When subjects were split into two age groups, however, prevalence of migraine was significantly higher among younger women (aged < 45) with stroke compared with their controls (13/20 v 6/20, odds ratio 4.3 (1.2 to 16.3), p = 0.03). Furthermore, the risk of ischaemic stroke was higher among younger women who smoked (7/20 v 1/20, odds ratio 10.2 (1.1 to 93.3)). Prevalence of migraine was not different between patients with stroke and matched controls except among women aged < 45, when migraine and stroke were significantly associated.