Study findings are indicating that patients with migraine are at an increased risk of Bell palsy, and the increased risk varies among age groups.
Bell palsy accounts for 60% to 75% of all cases of facial palsy, and approximately 11 to 40 people per 100,000 experience the condition globally each year. While the condition is thought to be triggered by viruses, the pathophysiology is complex, and several other triggers have been suggested.
Researchers of the study collected data on 45,164 patients with migraine from the Korean National Health Insurance National Sample Cohort from 2002 to 2013, which included patients who underwent treatment for migraine more than once. These patients were matched 1:4 with 180,656 patients who were not diagnosed with migraine during the same period.
Throughout the study period, 0.6% (262/44,902) of patients with migraine and 0.5% (903/179,753) of controls experienced Bell palsy. Patients with migraine had a risk of Bell palsy that was 1.16 times higher compared with the control group.
Looking by age group, patients with migraine who were between 30 and 60 years had a risk that was 1.28 times higher compared with the control group.
The elevated risk of Bell palsy remained even after adjusting for age, sex, income, residence, hypertension, diabetes, and dyslipidemia.
“Although previous studies considered that migraine headaches were triggered by dilation of cerebral vessels, recent evidence supports that migraine attacks can also occur in association with cardiovascular disturbances in the absence of vasodilation,” wrote the researchers. “Many studies have reported a risk of ischemic stroke in migraine patients. These complex etiologies and relationships to vascular ischemia may provide a link between migraine and Bell palsy.”
According to the researchers, the direct neural effects from the trigeminal nerve to the facial nerve could contribute to the risk of facial palsy among patients with migraine.
Other possible explanations for this increased risk can be traced to the psychological impact of migraines. “Several common psychological disorders, including depression, anxiety, bipolar disorder, and obsessive-compulsive disorder and attention-deficit/hyperactivity disorders, are increased in migraine patients,” wrote the researchers, who explained that these issues may also have synergistic effects and may be a risk factor for Bell palsy.