March 30, 2023 -- Researchers say they have found links between two types of headaches and the body’s internal clock, which could lead to better treatments.
Cluster headaches more commonly happen at night, and migraines occur more often during the day, according to a meta-analysis published in Neurology, the medical journal of the American Academy of Neurology.
Cluster headaches bring pain around the eyes in bursts that can last for 15 minutes; an attack can last up to three hours. These headaches are rare and more common in men than in women.
Migraines, meanwhile, are three times more common among women.
“Cluster headache is known to be circadian, but it was surprising how circadian migraine is,” Mark Burish, MD, the study’s lead author and director of the Will Erwin Headache Research Center at UTHealth Houston, told NBC News.
The meta-analysis looked at 72 studies that examined how the body’s internal clock, or circadian rhythm, is involved with headache disorders. Combined, the two headache types affect more than 40 million Americans.
Cluster headaches were more closely tied to circadian cycles during seasonal changes in the spring and fall. More than 70% of people in 16 studies said they had more attacks during these seasons and said they usually happen between late night and early morning.
Researchers were surprised that migraines came in cycles throughout the day and the year. Migraine headaches were reported less often from 11 p.m. to 7 a.m., with more frequent and worse migraines from spring through fall.
“Medications that target the circadian cycle might be a new type of treatment we can offer these patients,” Burish said. “We weren’t sure if looking at circadian targets of therapy for migraine would actually do anything but after putting all of this together, we are more confident that it could be,” he said.