Of the 800,000 strokes that occur each year in the US, about 2000 to 3000 may be related to migraine, according to the American Migraine Foundation.1 Now, new research indicates a specific link between migraine with aura and ischemic stroke. So how should doctors counsel their patients about this link and stroke prevention?
According to the new meta-analysis, people who suffered from migraine with aura had two times increased risk of ischemic stroke compared to migraine sufferers without aura.2 Women, in particular, were at increased risk. About three-quarters of migraine sufferers are women, and risk for ischemic stroke was double for women with migraine, compared to men with migraine. Being younger than 45 years old, smoking, and oral contraceptive use among women were also risk factors for stroke-related migraine.2
On the flip side, stroke may also increase the risk for headache. Up to 23% of adults develop persistent post-stroke headache, according to a recent review.3 While post-stroke headaches tend to have tension-type features with more frequent and severe symptoms than stroke-related headaches, risk factors are similar: female sex, younger age, pre-existing headache disorder, and comorbid depression.
Research further suggests that stroke may increase the risk for migraine in children. A recent retrospective study of 115 children aged 30 days to 18 years seen at Lurie Children’s Hospital of Chicago found that 30% experienced post-stroke headache after suffering an ischemic stroke.4 Among these patients, 32% had new onset headache. Headaches developed about six months after the patient’s stroke, and arteriopathy was significantly linked to post-stroke headache. The study could not distinguish headache characteristics, such as migraine with and without aura.
While persistent post-stroke headache was recently added to the International Classification of Headache Disorders, more research is needed to identify features that distinguish post-stroke headache from stroke-related migraine. Nevertheless, some experts believe the two may have similar pathophysiology.
One school of thought points to a vascular origin. According to this view, arterial spasm contributes to the development of migraine. As the blood vessel constricts, its lumen narrows, increasing the risk for blood clots and stroke. Factors that also increase the risk of clots, such as oral contraceptives, may further increase the risk of ischemic stroke.
The pathophysiology is less clear for post-stroke headache, but it may also involve a vascular origin as a result of blood vessel injury or inflammation from a stroke. Other origins may include stroke-related neuro-excitability and neuroinflammation, damage to neural pain pathways, and genetic risk factors.
Regardless of the origin, experts recommend managing traditional risk factors for vascular disease and stroke to prevent migraine-related stroke.5 That includes better management of lifestyle factors such as getting adequate exercise, not abusing alcohol, smoking cessation as well as keeping weight, blood pressure, blood lipids, and blood glucose under control.
For women, smoking cessation is especially important. Finding alternative birth control methods to oral contraceptives may also be an important option for some women. In particular, oral contraceptives with ethinylestradiol or estrogen supplements may increase the risk for blood clots in women who experience migraines with aura.
While more studies are needed to determine whether preventing migraine actually decreases the risk of stroke, experts also recommend appropriate headache management with preventive medication, cognitive behavioral therapy, and lifestyle changes.5
They also advise educating patients about the signs of stroke and transient ischemic attack, including changes in aura and increased frequency or duration of headaches, especially when accompanied by weakness on one side.
Physicians should also ask patients about their history of headaches and monitor for possible indicators of stroke, especially among older individuals who are already at increased risk for stroke.
“There are certain things we consider red flags,” says Dr. Mitchell Elkind, President-elect of the American Heart Association and a neurologist at the Columbia University College of Physicians and Surgeons.6 “If somebody has had infrequent headaches and they’re suddenly occurring more often, or if moderate headaches suddenly become severe, that could be an indication of a new problem. We obviously have to be concerned that it’s not a stroke, so they get evaluated pretty thoroughly.” However, he reassured: “It’s not like people with migraines should be waiting anxiously about the possibility of having a stroke, but it does occur.”6
1. American Migraine Foundation. Understanding your symptoms and whether your migraine may carry an additional stroke risk. https://americanmigrainefoundation.org/resource-library/migraine-stroke-reducing-risk. Accessed June 28, 2019
2. Schürks M, Rist PM, Bigal ME. Migraine and cardiovascular disease: systematic review and meta-analysis. BMJ. 2009;339:b3914.
3. Lai J, Harrison RA, Plecash, A et al. A narrative review of persistent post-stroke headache - a new entry in the International Classification of Headache Disorders, 3rd Edition. Headache. 2018;58:1442-1453.
4. Gelfand AA, Fullerton HJ, Jacobson A, et al. Is migraine a risk factor for pediatric stroke? Cephalalgia. 2015;35:1252-1260.
5. American Migraine Foundation. Understanding your symptoms and whether your migraine may carry an additional stroke risk. https://americanmigrainefoundation.org/resource-library/migraine-stroke-reducing-risk. Accessed June 28, 2019.
6. American Heart Association. What migraine sufferers need to know about stroke risk. https://www.heart.org/en/news/2019/06/21/what-migraine-sufferers-need-to-know-about-stroke-risk. Accessed June, 28 2019.