By E.J. Mundell
The 10-year study of almost 73,000 people cared for at ophthalmology clinics in North Carolina found that -- after accounting for certain medication use and other factors -- people with migraine had a 20 percent higher risk of having dry eye disease.
The relationship seemed to strengthen with age, especially for women. For men aged 65 or over, having migraines nearly doubled the odds of also having dry eye disease, and women of the same age had almost 2.5 times the risk, the researchers said.
The bottom line: "Physicians caring for patients with a history of migraine headaches should be aware that these patients may be at risk for [concurrent] dry eye disease," according to the study team led by Dr. Richard Davis. He's an ophthalmologist at the University of North Carolina, Chapel Hill.
The findings resonated both personally and professionally for Angela Bevels, an optometrist who runs a clinic treating dry eye disease in Tucson, Ariz.
"I myself suffered from migraine headaches for many years, when I also happened to have undiagnosed dry eye. I didn't connect the two conditions at the time, but this new research makes me believe they may have been related after all," she said.
"Reinforcing my impression is the fact that my migraines have drastically improved over the past two years -- the exact amount of time since I've been successfully treated for dry eye," Bevels said.
According to background information in the new study, anywhere from 8 percent to 34 percent of adults may be affected by dry eye. It's a disorder of the tear film on the eye's surface that "results in symptoms of discomfort, visual disturbance" and other ocular issues that can really lessen a person's quality of life, the study authors explained.
The new study couldn't prove that one condition causes the other, but links between dry eye and migraine have been noticed for years, the researchers said. About 14 percent of Americans are affected by migraines.
So what could be the link?
According to the report, similar "underlying inflammatory processes" at the cellular level are known to play key roles in both dry eye disease and migraine.
"Inflammatory changes in dry eye disease might trigger similar events in neuromuscular tissue, leading to the development and propagation of migraine headaches," the authors theorized. Or excessive dryness of the eye's surface might work on key nerve pathways to help trigger migraines, they added.
Whatever the connection, doctors need to be on the lookout that a patient with one of these conditions is at higher risk for the other, Davis and his colleagues concluded.
For her part, Bevels said that "studies like these are important because they shed new light on co-existing conditions with dry eye that clearly impact many Americans' quality of life."
The findings were published March 7 in JAMA Ophthalmology.