Migraines which start with flashing lights can raise the risk of having an irregular heartbeat.
People who suffer migraines with visual symptoms, including light flashes, blurry vision or blind spots, are 30 per cent more likely to have an irregular heartbeat than those who are migraine-free.
An irregular heartbeat can lead to a stroke, as blood clots start in the heart and make their way to the brain.
Migraines which start with flashing lights can raise the risk of having an irregular heartbeat
Women are three times more likely than men to suffer migraines, which usually begin in early adulthood.
They affect around one in five women and one in 15 men, with a minority suffering a visual ‘aura’ before their headache starts.
Researchers tracked the medical records of almost 12,000 people, of whom just over 1,500 suffered migraines, with 426 having visual symptoms.
They found an estimated nine out of 1,000 people with visual migraines also had an irregular heartbeat, compared to just seven out of 1,000 migraine sufferers who did not see an ‘aura’ before attacks.
Dr Souvik Sen, who led the study from the University of South Carolina, said: ‘It is important to note that people with migraine with aura may be at a higher risk of atrial fibrillation due to problems with the autonomic nervous system, which helps control the heart and blood vessels.
The pain of migraine
‘More research is needed to determine if people with migraine with visual aura should be screened for atrial fibrillation.’
For the study, 11,939 people with an average age of 60 were asked if they had ever suffered a migraine.
This is a headache lasting longer than four hours, with throbbing or pulsating pain mainly on one side of the head, along with nausea or vomiting or sensitivity to sound and light.
Of those who suffered migraines, 426 reported visual symptoms, which they said included seeing spots and jagged lines.
Among this group, 18 per cent developed an irregular heartbeat over the next 20 years, compared to 14 per cent of migraine sufferers without vision issues.
Among migraine-free people, 17 per cent developed an irregular heartbeat, also known as atrial fibrillation.
Dr Sen said: ‘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.’
The results show four out of 1,000 people every year suffered a stroke if they had migraines with visual auras.
Half as many, two out of 1,000 a year, suffered a stroke in people with non-visual migraines, and three out of 1,000 in people who did not suffer migraines.
If a migraine can lead to an irregular heartbeat, the latter can trigger a stroke, as blood may pool in the heart, potentially forming clots that go to the brain.