MAYWOOD, Ill. – People who suffer migraine headaches with auras are at roughly double the risk of suffering the most common type of stroke.
The risk is more than tripled in migraine sufferers who smoke. And migraine sufferers who smoke and use birth control pills are seven times more likely to suffer strokes.
Migraine headaches also increase the risk of heart attacks and arterial claudication (leg pain due to poor circulation).
Numerous individual studies and meta-analyses have demonstrated that people who have migraines with aura are at a higher risk for ischemic stroke. (A meta-analysis combines results of multiple studies.) Citing these and other studies, Loyola University Medical Center neurologists Michael Star, MD, and José Biller, MD, describe the association between stroke and migraine in a chapter in the new text Headache and Migraine Biology and Management.
About 85 percent of strokes are ischemic, meaning they are caused by blood clots in the brain. Migraine with aura is a migraine headache that is preceded by an aura, which typically includes flashes of light, bright spots, blind spots and perhaps tingling in the hands or face.
Recent studies also suggest there is a link between migraines and hemorrhagic strokes, which are caused by bleeding in the brain.
“The biology underlying the relationship between migraine and stroke is poorly defined,” Drs. Star and Biller write.
Researchers have proposed several possible explanations for the migraine-stroke association:
- Migraine sufferers are more likely to have risk factors for cardiovascular disease, including low levels of HDL (so-called “good cholesterol”) and high levels of c-reactive protein.
- Specific genes may predispose people to suffer both migraines and stroke.
- Medications to treat migraines may increase the risk of stroke.
- A phenomenon that occurs during migraine aura, called cortical spreading depression, might trigger an ischemic stroke. A cortical spreading depression is a slowly propagated wave of depolarization, followed by depression of brain activity occurring during migraine aura. It includes changes in neural and vascular function.
“Taking all of these possible explanations into account, the research may point to stroke and migraine sharing a reciprocal causal relationship,” Drs. Star and Biller write. “There is a significant amount of research attempting to further elucidate this multifaceted relationship.”
Dr. Star is a co-chief resident in neurology and Dr. Biller is a professor and chair in the Department of Neurology of Loyola University Chicago Stritch School of Medicine.
Headache and Migraine Biology and Management was published March 13, 2015, by Academic Press. Editor is Seymour Diamond, MD, a pioneer in headache medicine and executive chair of the National Headache Foundation.
Loyola University Health System (LUHS) is a member of Trinity Health. Based in the western suburbs of Chicago, LUHS is a quaternary care system with a 61-acre main medical center campus, the 36-acre Gottlieb Memorial Hospital campus and more than 30 primary and specialty care facilities in Cook, Will and DuPage counties. The medical center campus is conveniently located in Maywood, 13 miles west of the Chicago Loop and 8 miles east of Oak Brook, Ill. The heart of the medical center campus is a 559-licensed-bed hospital that houses a Level 1 Trauma Center, a Burn Center and the Ronald McDonald® Children’s Hospital of Loyola University Medical Center. Also on campus are the Cardinal Bernardin Cancer Center, Loyola Outpatient Center, Center for Heart & Vascular Medicine and Loyola Oral Health Center as well as the LUC Stritch School of Medicine, the LUC Marcella Niehoff School of Nursing and the Loyola Center for Fitness. Loyola’s Gottlieb campus in Melrose Park includes the 255-licensed-bed community hospital, the Professional Office Building housing 150 private practice clinics, the Adult Day Care, the Gottlieb Center for Fitness, Loyola Center for Metabolic Surgery and Bariatric Care and the Loyola Cancer Care & Research at the Marjorie G. Weinberg Cancer Center at Melrose Park.