A study recently published in the journal Neurology found a link between migraine during midlife and later-life parkinsonism.1
We’ve invited the lead author of that study, Ann Scher, PhD, Professor of Epidemiology at F. Edward Hebert School of Medicine, Uniformed Services University of the Health Sciences, to shed some light on the key findings. In this podcast, she gives a succinct overview of the study details and briefly discusses what the findings may suggest.
Who were the study subjects?
We studied adults from Reykjavik, Iceland—more than 5600 adults from the general population who were interviewed at 2 time points. They were first interviewed during middle-age (33 to 65 years old) and were asked about symptoms of migraine. They were later interviewed about 25 years later and were asked about symptoms related to Parkinson disease (PD) or parkinsonism, including diagnosis and family history, and were asked about 6 parkinsonian symptoms.
What were the key findings?
Men and women who reported having migraine at the first interview—particularly those with migraine with aura were more than twice as likely to have PD or parkinsonian symptoms. We also found women who had migraine with aura were more likely to have a family history of PD. For example, while those without headache had a 1.1% likelihood of being diagnosed with PD, those with migraine with aura had a 2.4% likelihood. About 8% of those without headache had 4 or more parkinsonian symptoms, whereas about 20% of those who had migraine with aura had parkinsonian symptoms.
Do you want to speculate on what your findings suggest?
We don’t believe that this link between migraine and parkinsonism is due to medications patients may be taking that may be blocking dopamine. We controlled for that. We also controlled for comorbid cerebrovascular disease. We don’t believe those 2 plausible explanations are involved in this particular study population. There may be some other shared vulnerability to migraine and PD that has yet to be determined, including possibly a history of head injury which we noted was more than twice as common in subjects who had migraine with aura.
Did you want to comment about RLS?
RLS is believed to be a related disorder to PD and parkinsonism. We did find that risk of RLS was elevated for those with headache generally, but it was not specific to migraine with aura or migraine overall. This was not a novel finding; a number of other studies have also found RLS to be linked with headache.
1. Scher AI, Ross W, Sigurdsson S, et al. Midlife migraine and late-life parkinsonism. Neurology. Sept 17, 2014. http://www.neurology.org/content/early/2014/09/17/WNL.0000000000000840.short. Accessed September 30, 2014.