Global, Regional, and National Burden of Alopecia Areata and its Associated Comorbidities, 1990-2021, and Projections to 2050: An Analysis of the Global Burden of Disease Study 2021.

There are no updated epidemiological data on alopecia areata up to 2021. The objective of this study was to emphasize the urgency of addressing the evolving public health challenges of alopecia areata. The annual point prevalence, incidence, and years lived with disability of alopecia areata from 204 countries and regions from 1990-2021 were extracted. Subgroup analyses based on gender, age, global, national, regional, sociodemographic index, and World Bank income were conducted. From 1990-2021, age-standardized prevalence, incidence, and years lived with disability of alopecia areata globally show a decreasing trend, with females dominating. There was a reduction in the disease burden in high sociodemographic index regions, but alopecia areata in general did not reflect a concentration in certain regions and was more equally distributed. Decomposition analysis revealed that population growth was the major contributor to the burden of alopecia areata, followed by population ageing. Patients with alopecia areata before the age of 14 were associated with anxiety disorders and other psychological disorders, but patients after the age of 14 were not associated with the onset of these disorders. Also, atopic dermatitis has been associated with alopecia areata. The epidemiological differences in psychological disorders between children and adolescents/adults with alopecia areata further demonstrate the importance of differentiated recognition at different ages.