Migraine Might Bring More Than Meets the Eye

Migraine has long been recognized as a risk factor for stroke. To clarify this relation, researchers conducted a case-control analysis using data from the Stroke Prevention in Young Women Study; 386 women (age range, 15–49) who had experienced ischemic stroke were compared with 614 matched controls. Women were classified as having no migraine history, having probable migraine without visual aura, or having probable migraine with visual aura (PMVA); visual aura was defined as “seeing spots, lines, or flashing lights around the time of probable migraine, or ever experiencing loss of vision.”

A total of 145 ischemic strokes were identified in women who had PMVA, yielding a 50% greater likelihood of stroke compared with that in women who did not have migraine. However, probable migraine without visual aura was not associated with likelihood of stroke. PMVA significantly increased the risk for stroke in women without a history of hypertension, diabetes, or myocardial infarction. The minimally adjusted risk for stroke of undetermined cause in women with PMVA was 1.6 (95% confidence interval, 1.1–2.3), but other stroke subtypes (large-artery atherosclerotic, cardioembolic, and lacunar) were not significantly associated with prior PMVA.

In an adjusted analysis, neither smoking nor oral contraceptive (OC) use had independent effects on the association between PMVA history and incident stroke. However, women with PMVA who smoked and used OCs had sevenfold higher odds of stroke (95% CI, 1.4–22.8) compared with women with PMVA who did not smoke and use OCs. Among the few women reporting a first PMVA within 12 months of stroke or of study enrollment, the odds ratio for stroke was 6.0 (95% CI, 1.9–18.6).