Sian Claire Owen, medical journalist for Cardio Debate, UK

Migraine affects around 15 percent of the global population and is a leading cause of disability. Symptoms include headaches with or without aura, and can also include gastrointestinal and autonomic symptoms. It is well established that migraine is associated with ischaemic stroke and ischaemic heart disease, however recent research published in The British Medical Journal has widened the scope and looked at the link between migraine and a broader range of cardiovascular diseases. [1]

A population-based matched cohort study analysed data from Danish administrative and medical registries, comprising 51032 patients in the migraine cohort and 510320 in the general population. They investigated the risk of CV diseases including ‘MI, ischaemic or haemorrhagic stroke, peripheral artery disease, venous thromboembolism, atrial fibrillation or atrial flutter, and heart failure’ in patients with a first-time diagnosis of migraine. This data was then compared with those in the general population.

Information regarding other risk factors such as obesity, hypertension, chronic obstructive pulmonary disease and alcoholism were also taken into account, as were adjustments for drugs which may impact on the relationship between migraine and CVD.

Of all the CV diseases investigated, migraine was linked with MI (HR 1.49, 95% confidence interval 1.36 to 1.64), ischaemic stroke (2.26, 2.11 to 2.41), haemorrhagic stroke (1.94, 1.68 to 2.23), venous thromboembolism (1.59, 1.45 to 1.74) and atrial fibrillation or atrial flutter (1.25, 1.68 to 2.23). [1]

Furthermore, migraine with aura was associated with higher CVD risk than without aura, and were higher in women than men.

The study authors recommend that in the light of these results, physicians may wish to consider anticoagulation treatment in these patients.



Cardio Debate Expert Comments

This is an interesting study that mostly reinforces what was already known, namely that people suffering from migraine carry an increased risk of cardiovascular diseases. To an extent it expands on what was known inasmuch as, whilst the link to ischaemic heart disease and ischaemic stroke was well established, the current study shows that migraneurs also carry a higher risk of haemorrhagic stroke, peripheral arterial disease, atrial fibrillation / flutter, heart failure and venous thromboembolism. However, it is clear from the literature that atherosclerosis is the principal pathological process underlying most of these diseases; so it is not entirely surprising that the increase in ischaemic heart disease and stroke associates with an increase in these other conditions. The exception of course is venous thromboembolism, and it is interesting to speculate on why this should associate with migraine. Although this study offers no mechanistic insights to this, one might offer a number of possible explanations:  decreased mobility of patients during migraine attacks, especially if they are frequent; higher prevalence of patent foramen ovale in migraineurs, especially those who experience auras; in women, the possible use of oral contraceptives or hormone replacement therapy, both of which are thrombogenic and liable to precipitate migraine attacks.

Whilst interesting and relevant, inasmuch as it should prompt physicians to screen their patients with migraine both for cardiovascular risk factors and for the presence of subclinical cardiovascular disease, it is clear from this research that the absolute risk levels for cardiovascular outcomes are low. Therefore, although the authors are correct to state that ‘clinicians should consider whether patients at particularly high risk of cardiovascular diseases would benefit from anticoagulant treatment’, this should not in any way be taken to mean that the management of migraine should as a matter of routine include antiplatelet or anticoagulant treatment.