For women, migraine with aura is a greater cardiovascular risk factor than other conventional CVD factors such as obesity and dyslipidaemia, a US study suggests.
A retrospective cohort study of 27 858 female health professionals over the age of 45 year found that migraine with aura was associated with a higher incidence rate of major cardiovascular events (myocardial infarction, stroke, cardiovascular death) compared with women without migraine or with migraine without aura.
Published in JAMA, the findings from a 23-year follow up of a Women’s Health Study cohort that included 1435 women with migraine with aura, showed the increased cardiovascular risk was evident after adjusting for other major cardiovascular risk factors and confounding.
The adjusted incidence rate of major cardiovascular events was significantly higher for women with migraine with aura compared to women with migraine without aura or no migraine (3.36 vs 2.11 per 1000 person-years, P < 0.001).
The only factors that exceeded migraine with aura in terms of cardiovascular incidence rates were diabetes and smoking (5.76 and 4.29 per 1000 person-years, respectively)
Migraine with aura was associated with higher rates of myocardial infarction, stroke and cardiovascular death compared to factors such as obesity (2.29) high triglycerides (2.67) and low high-density lipoprotein cholesterol (2.63).
The CVD incidence was not significantly different from people with elevated systolic blood pressure (3.78) high total cholesterol (2.85) or family history of myocardial infarction (2.71 per 100 person years).
The study authors noted that migraine with aura conferred an additional risk when added to factors such as diabetes (2.57 extra cases per 1000 person-years) and obesity (1.01 additional cases per 1000 person-years).
The additional effect of migraine with aura on cardiovascular risk was particularly strong when several vascular risk factors were present. The incidence rate of major CVD increased from 39.55 to 62.96 cases per 1000 person-years when migraine with aura was added to a combination of all vascular risk factors, except for a family history of premature myocardial infarction.
The study investigators said an association of migraine with aura on CVD events had been seen in previous studies, but it was not clear if this was because migraine often co-existed with other risk factors such as dyslipidaemia. This was the first to investigate migraine with aura against the adjusted incidence rates of CVD due to other cardiovascular risk markers, and showed that its contribution was not insignificant when compared to other risk factors.
The precise mechanisms linking migraine with aura to CVD incidence were still not well understood, they said, but might include impairments of the endovascular function, inflammatory processes and genetic predisposition.
“Cortical spreading depolarisation, the electrophysical mechanisms involved in migraine aura, can play a role in stroke and potentially in other vascular events,” they wrote.
Migraine medication use may also be a factor in CVD risk, although patients with migraine without aura had a lower CVD risk, they noted.