Global, regional and national burden of alopecia areata and its associated diseases, 1990-2019: A systematic analysis of the Global Burden of Disease Study 2019.

BACKGROUND: No study to date has concomitantly reported the global burden of alopecia areata (AA) and its associated diseases. METHODS: The crude and age-standardized rates of prevalence (ASPR), incidence (ASIR) and years lived with disability (YLDs) of AA were extracted from the global burden of disease, injuries and risk factors study (GBD) database between 1990 and 2019 for 204 countries and territories. We stratified the analysis by global region, nation, sex, age and sociodemographic index (SDI) to dissect the epidemiology of AA and its associated diseases. RESULTS: Alopecia areata was responsible for 0.024% of the total DALYs. Age-standardized DALYs rate of AA was 7.51 [4.73-11.14] per 100,000. Overall ASPR, ASIR and age-standardized YLDs rates were stable from 1990 to 2019 globally. All three rates were about two times higher in females compared to males and had a bimodal distribution with peaks at age 30-34 years and 60-64 years. AA burden was positively correlated with SDI (r = .375, p < .001) and was most prevalent in high-income countries, especially North America. Countries with a high AA incidence were more likely to have high incidences of autoimmune diseases and low incidences of ischaemic heart disease and ischaemic stroke. CONCLUSIONS: The burden of AA was prominent in females, young adults, high sociodemographic countries and North Americans. The study corroborates sex- and region-specific implications and public health measures for AA and its associated burdens. These epidemiological data on AA burden can guide future research efforts, prevention strategies and allocation of resources.