Summary: New research finds that people who experience migraine with visual aura have a higher risk of developing atrial fibrillation, an irregular heart rhythm linked to stroke.
Source: AAN
Migraine with visual aura linked to higher atrial fibrillation risk
People who experience migraine with visual aura—visual disturbances that occur just before the onset of head pain, such as flashing lights, wavy lines, blurred vision or blind spots—may face an increased risk of atrial fibrillation (AF), according to a study published online in Neurology on November 14, 2018. Atrial fibrillation is a common type of arrhythmia in which the heart’s normal rhythm becomes irregular, allowing blood to pool in the heart and potentially form clots that can travel to the brain and cause ischemic stroke.
“Since atrial fibrillation is a common source of strokes caused by blood clots, and previous research has shown a link between migraine with aura and stroke, we wanted to see if people who have migraine with aura also have a higher rate of atrial fibrillation,” said study author Souvik Sen, MD, MS, MPH, of the University of South Carolina in Columbia. “Atrial fibrillation can be managed through medication, but many people do not realize that they have atrial fibrillation.”
Study design and participants
The analysis used data from the Atherosclerosis Risk in Communities (ARIC) study, a longitudinal, community-based cohort. Researchers evaluated 11,939 participants (average age 60) who had no prior history of atrial fibrillation or stroke. Headache history was assessed in 1993–1995, and participants were followed for incident AF through 2013—up to 20 years of follow-up.
Among the participants, 426 reported migraine with visual aura, 1,090 reported migraine without visual aura, 1,018 had non-migraine headache, and 9,405 reported no headache. Over the follow-up period, incident AF was observed in 232 (15%) of the 1,516 participants with any migraine and in 1,623 (17%) of the 9,405 participants without headache.
Key findings and risk estimates
After adjusting for age, sex, blood pressure, smoking and other potential confounding factors, the study found that migraine with visual aura was associated with a significantly higher risk of developing atrial fibrillation:
- Compared with people who reported no headache, those with migraine with visual aura had a 30% higher risk of incident AF (hazard ratio 1.30, 95% confidence interval 1.03–1.62).
- Compared with people who had migraine without visual aura, those with migraine with visual aura had a 39% higher risk of AF (hazard ratio 1.39, 95% confidence interval 1.05–1.83).
Translating these figures into absolute risk, the results correspond to an estimated nine out of 1,000 people with migraine with aura having atrial fibrillation annually, compared to seven out of 1,000 people with migraine without aura. The researchers also reported stroke incidence rates of about four out of 1,000 people per year in the migraine-with-aura group, compared with two out of 1,000 per year in those with migraine without aura, and three out of 1,000 per year among those with no headache history.
Implications and possible mechanisms
The investigators suggest that atrial fibrillation could be one pathway linking migraine with visual aura to increased stroke risk. “Our research suggests that atrial fibrillation may play a role in stroke in those with migraine with visual aura,” said Sen. The authors note that autonomic nervous system dysfunction—which helps regulate heart rate and blood vessels—may contribute to the elevated AF risk seen in people who experience visual aura with migraine.
If confirmed by further research, these findings could influence clinical decision-making about screening for atrial fibrillation in patients with migraine with visual aura, since AF is often asymptomatic and treatable with medications or other interventions to reduce stroke risk.
Limitations
The study has several limitations. The migraine definition used may have excluded people whose migraine history was limited to episodes lasting less than one year or who experienced migraine earlier in life and were not captured. Information about migraine medications—which can potentially affect heart rate and rhythm—was limited, so the impact of treatment on AF risk could not be fully assessed.
Source: AAN
Publisher: Organized by NeuroscienceNews.com
Image Source: NeuroscienceNews.com image is in the public domain.
Original Research: “Migraine with visual aura a risk factor for incident atrial fibrillation: A cohort study” by Souvik Sen et al., published in Neurology, November 14, 2018.
doi: 10.1212/WNL.0000000000006650
Abstract
Objective
Migraine with visual aura has been associated with cardioembolic stroke risk. The objective of this study was to assess the association between migraine with visual aura and incident atrial fibrillation in the Atherosclerosis Risk in Communities cohort.
Methods
Participants in the ARIC study were interviewed about migraine history in 1993–1995 and were monitored for incident AF through 2013. AF was identified using ECGs, hospital discharge codes, and death certificates. Multivariable Cox proportional hazards models examined the relation between migraine subtypes and incident AF, compared with controls without headaches. A mediation analysis evaluated whether AF might mediate the association between migraine with visual aura and stroke.
Results
Of 11,939 participants assessed for headache and free of AF or stroke at baseline, 426 reported migraine with visual aura, 1,090 reported migraine without visual aura, 1,018 reported non-migraine headache, and 9,405 reported no headache. Over up to 20 years of follow-up, incident AF occurred in 232 (15%) of the 1,516 participants with migraine and in 1,623 (17%) of those without headache. After adjustment for multiple confounders, migraine with visual aura was associated with increased risk of AF compared with no headache (hazard ratio 1.30, 95% CI 1.03–1.62) and compared with migraine without visual aura (hazard ratio 1.39, 95% CI 1.05–1.83). The findings suggest AF may partially mediate the migraine-with-aura-associated stroke risk.
Conclusions
Migraine with visual aura was associated with an increased risk of incident atrial fibrillation, a condition that can contribute to ischemic stroke. Further research is needed to clarify mechanisms and to determine whether targeted AF screening in this population would reduce stroke risk.