Migraine headaches have been linked to double the risk of a nervous system condition that causes facial paralysis, called Bell's palsy, according to a new study published in the December 17, 2014, online issue of Neurology. 

Bell's palsy affects between 11 and 40 per 100,000 people each year. Most people with Bell's palsy recover completely.  Headaches are the most common disorder of the nervous system, affecting about 12 percent of the US population. 

"This is a very new association between migraine and Bell's palsy," said study author Shuu-Jiun Wang, MD, with National Yang-Ming University and Taipei Veterans General Hospital in Taipei, Taiwan. "Our study also suggests that these two conditions may share a common underlying link."

For the study, two groups of 136,704 people ages 18 and older, one group with migraine and one without, were followed for an average of three years. During that time, 671 people in the migraine group and 365 of the non-migraine group were newly diagnosed with Bell's palsy. People with migraine were twice as likely to develop Bell's palsy even after researchers accounted for other factors that could increase the risk of the condition, such as sex, high blood pressure and diabetes.

"Infection, inflammation or heart and vascular problems could be shared causes for these diseases," Wang said. "If a common link is identified and confirmed, more research may lead to better treatments for both conditions."