While cluster headache is more common in men than in women, a new study suggests the disorder may be more severe for women. Photo by kizzzbeth/Flickr
Dec. 21 (UPI) -- While cluster headache -- which is extremely painful and can last for many days, or even weeks, in a row -- is more common in men than in women, a new study suggests the disorder may be more severe for women.
The findings appeared Wednesday in Neurology, the medical journal of the American Academy of Neurology.
Cluster headaches occur in groups, or clusters, with each attack lasting roughly one to three hours, on average, medical experts say. They may occur anywhere from every other day to multiple times a day, and cluster periods are followed by remissions that may last months or years.
"For many patients, a cluster bout can arise during a certain time of the year while headache attacks recur with clock-like regularity at the same time of the day," the research paper explains.
According to the study, such attacks lasted longer for women than for men: 8% of women said their headache bouts lasted an average of four months to seven months, compared with 5% of men saying so.
Moreover, 18% of women in the study -- versus 9% of men -- had chronic cluster headache -- defined as recurring cluster headache attacks for one year or more without interruption, or with short, symptom-free intermissions that last less than three months.
"Cluster headache is still often misdiagnosed in women, perhaps because some aspects can be similar to migraine," Andrea C. Belin, the study's corresponding author and a senior researcher and group leader in the department of neuroscience at Karolinska Institute in Stockholm, Sweden, said in a news release.
While the ratio of men to women with cluster headache has been shifting over the years, it is still considered mainly a disorder of men, making it more difficult for women with milder symptoms to get the diagnosis, Belin said.
"It's possible this could contribute to the higher rate of chronic cluster headache in women," she said.
The significant differences between males and females in how cluster headache presents should be considered at the time of diagnosis and when choosing therapy options so the most effective treatment can be given as quickly as possible, the researchers said.
The study involved 874 people, averaging about 50 years old, who had been diagnosed with cluster headache; two-thirds of the participants were male.
They answered a detailed questionnaire about their symptoms, medications, headache triggers and lifestyle habits.
Based on the study participants' responses, the researchers discovered that women were significantly more likely to have a circadian pattern of attacks, with early morning onset and reduced total sleep time.
Women were more likely than men to experience ptosis, when the upper eyelid droops over the eye, and restlessness; and they were more likely to have a family member with a history of cluster headache.
The researchers also found that significantly fewer males used oxygen therapy and preventive medication than did females: 47.7% versus 60.2%.
Women were significantly more likely to have cluster headaches triggered by well-known migraine triggers, such as stress, weather changes, and sleep deprivation -- and women were also more likely to have a diagnosis of migraine, too.
Alcohol as a trigger for cluster headache occurred more frequently in males than in females, 54% vs. 48%, while lack of sleep triggering an attack was more common in females, 31% vs. 20%, the researchers said.
The researchers conceded a limitation of their study is that information was self-reported by the participants, who may not have remembered everything correctly.