ArticleNeurology2026
The Prevalence and Incidence of Cluster Headache: A Norwegian Population-Based Time-Trend Study.
Article in Neurology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
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Abstract
BACKGROUND AND
objectivesData on time trends in cluster headache epidemiology are sparse. The aim of this study was to report trends in prevalence and incidence of cluster headache in Norway over a 14-year period.
methodsWe conducted a registry-based study using linked data from the Norwegian Registry for Primary Health Care, the Norwegian Control and Payment of Health Reimbursements Database, the Norwegian Patient Registry, the Norwegian Prescribed Drug Registry, and Statistics Norway from 2009 to 2022. Data included diagnostic codes, prescriptions, and education. Adults (age ≥18 years) were included. Cluster headache prevalence was defined as ≥2 contacts (clinical consults or prescriptions) for cluster headache in a 365-day period. Age-standardized trends in prevalence and incidence by sex and year, and interactions between education and year, were analyzed with negative binomial regression. We estimated prevalence rate ratio (PRR) and incidence rate ratio per calendar year with 95% CIs.
resultsThe number of patients with cluster headache increased from 1,029 in 2009 (median age 44 years; 39.7% women) to 1,833 patients in 2022 (median age 47 years; 50.1% women). The annual age-standardized prevalence rate increased from 27.0 to 42.5 per 100,000 in the same period. Women had a 3-fold higher annual increase of 6% (PRR 1.06, 95% CI 1.05-1.07) compared with 2% (PRR 1.02, 95% CI 1.02-1.03) in men. The prevalence rate was higher in women than in men by 2022 (43.4 vs 41.7 per 100,000). The annual prevalence of chronic cluster headache and refractory chronic cluster headache varied between 6%-7% and 1%-2% of all cluster headache cases, respectively. The annual age-standardized incidence rate of cluster headache increased in women, from 10.1 to 14.6 per 100,000 from 2012 to 2022 and decreased in men, from 13.5 to 11.0 per 100,000. Incidence and prevalence rates were higher among individuals with lower education. DISCUSSION: Prevalence increased over 14 years, possibly reflecting improved diagnostic practices and awareness. These findings challenge previous reports of cluster headache predominantly affecting men, illustrating distinct shifts and trends in disease epidemiology. A limitation was the lack of clinical validation of cluster headache diagnostic codes in primary health care.
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