HEAD-WINd®: A nationwide cohort study of headache disorders in danish adults using survey, smartphone and registry data.

BackgroundThe HEAD-WINd® study was designed to examine the burden, characteristics and lived experiences of headache disorders in the Danish adult population. By integrating data from surveys, a smartphone application, and national health and social registries, the study addresses limitations of prior epidemiological research.MethodsA random sample of Danish residents aged 18-75 years were invited to participate ("base population"). Two nested cohorts were recruited using a population-based approach: (i) a survey cohort consisting of individuals reporting active headache disorders ("headache population") and (ii) a smartphone application cohort, derived from the headache population, which was followed longitudinally for 12 weeks. Data from these cohorts were enriched with data from national health and social registries, including information on medication use, hospital records, socioeconomic status and healthcare utilization. An adapted version of the Headache-Attributed Restriction, Disability, Social Handicap and Impaired Participation (HARDSHIP) questionnaire was used to classify multiple headache disorders and assess headache-attributed burden.ResultsOf the 100,030 invited individuals, 28,617 (28.6%) completed the general survey. Among them, 15,571 (54.4%) reported experiencing headache in the preceding year; 14,074 (90.4%) completed the headache-specific survey. In total, 663 individuals (4.7%) participated in the app-based longitudinal study. The mean ± SD participant age was 53.2 ± 15.5 years, 57.4% were women and the mean ± SD body mass index was 26.8 ± 7.4 kg/m².ConclusionsHEAD-WINd® has established a comprehensive, population-based cohort of Danish residents, including individuals both with and without headache disorders. This resource provides a framework for generating population-level insights into the burden and management of headache disorders.