Link Between Migraines and Cardiovascular Disease Strengthened by Nurses’ Health Study II Analysis
Migraine has long been associated with increased risk for stroke, but growing evidence suggests it also may play a role in upping the risk of cardiovascular disease in women.
“Migraine should be considered a marker for increased risk for CVD,” lead author Tobias Kurth, MD (Charité - Universitätsmedizin Berlin, Germany), told TCTMD in an email.
His study, published online May 31, 2016, before print in the BMJ, supports the idea that predisposition to migraine somehow impairs the endovascular system, triggering the onset of cardiovascular disease even among young, otherwise healthy women. The same physiologic mechanism is believed to be responsible for increasing risk of stroke among migraineurs, although exactly how that occurs is poorly understood, as is the role of aura.
A handful of studies in men and women have previously suggested that migraine sufferers have more cardiovascular disease risk, but data are sparse.
The 115,541 women in Kurth’s study were all nurses who enrolled in the Nurses’ Health Study II between the ages of 25 and 42 years and were followed from 1989 to 2011. All were free of angina and cardiovascular disease. Approximately 15% had a baseline diagnosis of migraine; information on prevalence of aura was not available.
Compared with women who did not have migraine, those who did had a 50% increase in the prevalence of the combined primary endpoint of major cardiovascular disease (MI, stroke, or fatal cardiovascular disease). They also had increases in individual cardiovascular outcomes despite adjustment for multiple variables including age, postmenopausal hormone use, and smoking status, and higher rates of mortality attributed to cardiovascular disease.
Kurth and colleagues say the findings are consistent with those of the Women’s Health Study, which reported a 42% and 63% increased risk of major cardiovascular disease events and mortality, respectively, among those with reported migraine. However, in that study, the association was apparent only for women who reported migraine with aura.
To TCTMD, Kurth said that although the current study focused only on women, there is no reason to believe the findings cannot be extrapolated to men. In fact, in earlier research, his group saw a similar association between migraine and CVD events in healthy men age 40 to 84 years enrolled in the Physicians’ Health Study.
But he stressed that since the exact mechanisms by which migraine increases CVD risk are unclear, “currently no specific medication should be initiated solely based on this risk marker. Rather the entire risk profile should be considered and treated accordingly.
Can a Brain Condition Affect the Heart?
In an editorial accompanying the study, Rebecca C. Burch, MD (Harvard Medical School, Boston, MA), and Melissa L. Rayhill, MD (State University of New York at Buffalo, Buffalo, NY), say the new data “strengthen the view that migraine is a risk factor for vascular disorders beyond those that affect the brain.” They note that some evidence suggests endothelial dysfunction or abnormal vascular reactivity in patients with migraine can increase the predisposition to the neurologic events of aura, as well as to vascular disease.
Burch and Rayhill say the study also raises questions about whether therapies aimed at decreasing the frequency or severity of migraine also reduce vascular risks later on, and urge clinicians to be cautious about assuming that aspirin or statins, for example, will benefit migraine patients. At least one study, an exploratory subgroup analysis from the Women’s Health Study, suggests the opposite may be true, since taking aspirin actually appeared to increase the risk of MI among women in that analysis who had migraine with aura.
Like Kurth, they say the limited evidence “suggests the need for therapeutic restraint until we have a better understanding of the mechanisms underlying the link between migraine and vascular disease.”
- Kurth T, Winter AC, Eliassen AH, et al. Migraine and risk of cardiovascular disease in women: prospective cohort study. BMJ. 2016;Epub ahead of print.
- Burch RC, Rayhill ML. Migraine and vascular disease: The medical implications of migraine are not limited to the brain. BMJ. 2016;Epub ahead of print.
- Kurth, Burch, and Rayhill report no relevant conflicts of interest.