A pain condition common in people with migraines also has a high prevalence in patients with cluster headache, according to a study conducted by researchers at the Jefferson Headache Center at Jefferson Hospital for Neuroscience.
Approximately half of a group of patients with cluster headaches experienced cutaneous allodynia, a condition that causes patients to have pain as a response to normally inconspicuous sensations, according to Michael Marmura, M.D., assistant professor of Neurology at Jefferson Medical College of Thomas Jefferson University.
The study, which was published in the Journal of Headache and Pain, included 41 patients with either chronic or episodic cluster headaches. The researchers tested for allodynia by brushing a gauze pad over the forehead, neck and forearms. Patients then reported if the gauze was painful or unpleasant, or not.
Twenty of the patients experienced allodynia, with the most common site of pain being the forehead. There were no significant differences between patients who experienced allodynia and patients who did not. The majority of patients were using preventive medications, which is a limitation of the study.
According to Dr. Marmura, allodynia has typically been described in migraines, but this is the largest study to date showing that allodynia occurs in cluster headache.
"It was surprising to find that allodynia was so common in patients with cluster headaches," Dr. Marmura said. "This could have important treatment implications, and suggests that there may be overlap in mechanisms for pain between migraines and cluster headaches."