Background: A history of migraine has been proposed as a risk factor for cerebral ischaemia in women under 45.
Methods: To investigate the association between history of migraine and cerebral ischaemia, we performed a case-control study of 308 patients aged 15-44, with either transient ischaemic attack (TIA) or stroke, and of 591 age- and sex-matched controls prospectively recruited in seven university hospitals. Crude and adjusted odds ratios were calculated using logistic regression analysis.
Findings: A history of migraine was more frequent in patients than in controls (14.9% vs 9.1%; adjusted odds ratio 1.9, 95% confidence interval 1.1-3.1). In the prospectively designed subgroup analyses, a history of migraine reached the highest odds ratio (3.7, 95% CI 1.5-9) and was the only significant risk factor in women below age 35 (p=0.003); atherogenic risk factors were more relevant in men and in patients older than 35; previous migraine attacks with aura were more frequent in stroke patients (odds ratio 8.6, 95% CI 1-75).
Interpretation: Our findings indicated that the rare association between migraine and cerebral ischaemia is limited to women below age 35, and suggest a need for careful clinical evaluation of comorbidity in the presence of migraine with aura.