Migraine and stroke

There is evidence that women with a self-reported history of migraine have a higher risk of ischaemic stroke (1)

• prospective, case-controlled study of 291 women with migraine 20-44 years matched with 736 hospital controls
• the outcome measure was self-reported history of headache - 25% of patients with stroke gave a history of migraine compared with 13% of controls. The odds ratio for ischaemic stroke was 3.54 (95% confidence interval 1.30-9.61)
• the study showed that women with migraine have an increased risk of ischaemic stroke. There was no evidence of an increased risk of haemorrhagic stroke

A more recent systematic review and meta-analysis of observational studies (2) revealed that migraine may be a risk factor in developing stroke:

• risk of stroke is increased in people with migraine (relative risk 2.16, 95% confidence interval 1.89 to 2.48). This increase in risk was consistent in people who had migraine with aura (relative risk 2.27, 1.61 to 3.19) and migraine without aura (relative risk 1.83, 1.06 to 3.15), as well as in those taking oral contraceptives (relative risk 8.72, 5.05 to 15.05)

Reference:

1. BMJ 1999; 318: 13-18.
2. Etiminan M et al. Risk of ischaemic stroke in people with migraine: systematic review and meta-analysis of observational studies. BMJ 2005; 330:63.