Propranolol: A Potential Shield Against Ischemic Stroke in Women Prone to Migraines

Research found that propranolol, a beta blocker used for high blood pressure and migraine prevention, exhibits a notable protective effect against ischemic strokes in women, especially in those experiencing migraines without aura. In contrast, this protective benefit was not observed in men.

Migraine headaches are prevalent in the population, yet they are three times more frequent in women than men. This painful condition is linked to a heightened stroke risk. While propranolol can prevent migraines, its impact on overall stroke risk remains uncertain.

“Migraine is often overlooked as a cardiovascular risk factor, and until recently, preventive options for migraine sufferers were lacking,” stated Mulubrhan Mogos, Ph.D., M.Sc., FAHA, the study’s lead author and assistant professor at Vanderbilt University School of Nursing in Nashville, Tennessee. “It’s crucial for women, particularly those who experience migraines without aura, to be aware of the potential benefits of propranolol. This finding is significant for those managing migraines.”

Mogos also highlighted the fact that migraine disproportionately impacts women from historically under-resourced backgrounds, which can hinder their educational and employment opportunities, perpetuating a cycle of disadvantage. Although newer treatment options have shown success, their high costs may limit access for women in these communities.

The investigation involved analyzing over 3 million electronic health records from two extensive databases. Researchers identified individuals with migraines who suffered a stroke versus those who did not (the control group) and assessed whether propranolol usage for migraine prevention influenced stroke risk.

“We started by examining overall stroke incidences, then narrowed our focus to ischemic strokes. After controlling for potential confounding factors, we found a significant association, particularly for ischemic strokes,” Mogos explained.

After adjusting for various factors, including demographics (age, sex, race), health conditions (like high blood pressure and diabetes), and hormonal variables (such as birth control usage and pregnancy), the analysis revealed:

• Propranolol was significantly linked to a lower risk of ischemic stroke in women with migraines, especially those without aura. Women on the medication showed a 52% lower risk in one database analysis and a 39% lower risk in another. There was no observed reduction in stroke risk for men in either analysis.
• The protective effect was notably stronger against ischemic strokes for women with migraines lacking aura, which can present as disturbances like flashing lights or zigzag patterns, along with symptoms like tingling or confusion.
• Secondary analyses indicated that women taking propranolol exhibited lower overall stroke rates across multiple timeframes in both databases.

“Our results underscore the importance of discussing preventive migraine therapies with women and healthcare providers. It’s vital that effective treatments are accessible to under-resourced communities suffering disproportionately from this condition. Doing so could help alleviate healthcare disparities,” Mogos remarked.

“Migraine without aura often goes unnoticed as a stroke risk factor, especially in women. Previous literature has shown that migraines pose a greater risk for women compared to men. The study’s findings are not surprising; previous evidence suggests that medications like propranolol, initially intended for blood pressure management, can significantly reduce stroke risk. This research is promising for women dealing with frequent migraines, as it highlights a medication that aids in preventing both migraines and strokes. Moreover, the study exemplifies the benefits of investigating health issues separately for women and men, enabling personalized healthcare based on recognized sex differences in stroke risk factors,” said Tracy E. Madsen, M.D., Ph.D., who is chair of the American Heart Association Clinical Cardiology (CLCD)/Stroke Women’s Health Science Committee and associate professor of emergency medicine at The Robert Larner, M.D. College of Medicine at The University of Vermont, though she was not involved in the study.

The primary limitation of this study is the retrospective data analysis using electronic health records, which might lead to biases such as misclassification due to relying on ICD codes (used for classifying health conditions). This underscores the need for future studies implementing a forward-looking approach to validate these findings.

Additional details about the study include:

• This research evaluated how migraine treatments impact stroke risk by utilizing two de-identified electronic health record databases: the Synthetic Derivative (SD) from Vanderbilt University Medical Center (VUMC) and the All of Us Research Program overseen by the National Institutes of Health (NIH).
• The study was conducted at the Vanderbilt University School of Nursing and the Department of Biomedical Informatics at Vanderbilt University Medical Center in Nashville.
• The SD database contains longitudinal research data on over 3 million individuals from more than 15 years. By May 2024, the All of Us Research Program had electronic health record data from over 230,000 diverse participants nationwide.
• The SD database represents a more localized population, while the All of Us database encompasses a wider variety of participants from different U.S. regions, which may contribute to observed differences.
• Men and women with primary stroke diagnoses following their first migraine were included; those in the control group had no stroke diagnosis post-migraine onset.