Risk of peripheral artery disease and stroke in migraineurs with or without aura: a nationwide population-based cohort study

Background: Migraine is deemed a neurovascular disorder and there is growing evidence on the increased risk of cardiovascular disease, especially ischemic stroke, in patients with migraine. However the risk of peripheral artery disease (PAD) and stroke in migraineurs and the association between migraineurs with or without aura is still under debate. Our study aimed to identify the risk of PAD and stroke in migraineurs with or without aura. Methods: This was a population-based cohort study utilizing Taiwan Longitudinal Health Insurance Database (LHID2010). Patients with coding of migraine from 2002 to 2011 were enrolled and those with established cardiovascular disease defined as myocardial infarction, stroke, PAD, venous thromboembolism, atrial fibrillation and heart failure diagnosis before the index date were excluded. Participants were categorized into migraine group, migraine without aura group, and migraine with aura group respectively. The subjects in the three groups were propensity score-matched randomly to their counterparts without migraine. The study outcome was PAD and stroke. The Cox proportional hazard model was used to estimate the hazard ratios with 95% confidence interval (CI) for the association between migraine and the incident events of disease, after controlling for related variables. Results: The migraine, migraine without aura, and migraine with aura group included 5,173 patients, 942 patients and 479 patients respectively after propensity score-matching. The migraine group had an increased risk of PAD [adjusted hazard ratio (aHR): 1.93; 95% confidence interval (CI): 1.45-2.57; p < 0.001] and stroke (aHR: 1.55; 95% CI: 1.35-1.77; p < 0.001) compared to their non-migraine controls. Both the groups of migraine without aura and with aura had an increased risk of stroke (aHR: 1.49, 95% CI: 1.11-2.00; p = 0.008; aHR: 1.63, 95% CI: 1.10-2.43; p = 0.016). With regards to the outcome of PAD, the group of migraine with aura had a trend of an increased risk but did not reach statistical significance (aHR: 1.95, 95% CI: 0.86-4.40; p = 0.108). Conclusion: Migraineurs without established cardiovascular disease had a significantly increased risk of PAD and stroke, and the risk of stroke persists in migraineurs with or without aura, with an increased trend of PAD in migraineurs with aura. Our study result should remind clinical physicians of the risk of PAD in the future among migraineurs even without established cardiovascular disease currently, and screening for PAD and stroke may be needed in caring patients with migraine.