Migraine should be considered a potent and persistent risk factor for cardiovascular diseases including heart attacks and stroke, a study published in the BMJ suggests.
An association between migraine in both men and women was shown in an observational study of data from over 51,000 Danish people diagnosed with migraine.
When compared with a control group of over 510,000 people who were migraine free, researchers found that migraine was associated with increased risks of cardiovascular diseases, particularly stroke, in the first year after diagnosis, and the risk persisted over almost two decades.
Over 19 years of follow-up, migraine was positively associated with myocardial infarction (Hazard Ratio 1.49,), ischaemic stroke (HR 2.26), and haemorrhagic stroke (HR 1.94,), as well as venous thromboembolism (HR 1.59) and atrial fibrillation or atrial flutter (HR 1.25).
The associations, particularly for stroke outcomes, were stronger during the first year after diagnosis than the long term. The associations of migraine with cardiovascular events were also stronger in patients with aura than in those without aura, and in women than in men.
Although the absolute risks were low, the findings suggest that migraine should be considered an important risk factor for cardiovascular disease at the population level, given that about a billion people worldwide have migraine, the researcher say.
The association between migraine and cardiovascular disease risk might be explained by several mechanisms, they suggest.
“The prevalence of patent foramen ovale is also higher for migraine with than without aura … which may cause paradoxical embolism, leading in turn to cerebral or coronary ischaemic events,” they note.
Patients with migraine often use NSAIDs, which are known to increase cardiovascular risk.
“Current migraine guidelines do not recommend use of aspirin and clopidogrel in the prophylaxis of migraine, but clinicians should consider whether patients at particularly high risk of cardiovascular diseases would benefit from anticoagulant treatment,” they suggest.
An accompanying editorial says there is now have plenty of evidence that migraine should be taken seriously as a strong cardiovascular risk marker.
“However, whether migraine itself is the problem or whether the disease is a marker of another underlying cause remains unclear,” says Professor Tobias Kurth of the Institute of Public Health, Charité – Universitätsmedizin Berlin.
But more research is needed to inform recommendations on how to reduce the risk of cardiovascular disease for people with migraine, he said.
“Simply advising this patient population to reduce other vascular risk factors seems like a shot in the dark. In adults with hypertension, prescribed antihypertensives and lifestyle changes are effective in lowering cardiovascular risk. Could people with migraine experience a similar reduction in cardiovascular risk if the frequency or severity of migraine is reduced? We simply do not know.”