S3 guideline diagnostics and therapy of alopecia areata - Part 1: Diagnostics and epidemiology.

In the project funded by the Innovation Committee at the G-BA, the S3 guideline for the diagnosis and treatment of AA was developed between 2023 and 2025. The interdisciplinary expert panel consisted of representatives from the German Dermatological Society, in particular from the Pediatric Dermatology Working Group, the Professional Association of German Dermatologists, the German Society for Psychosomatic Medicine and Psychotherapy, the German Society for Pediatrics and Adolescent Medicine, the Austrian Society for Dermatology and Venereology, a hairdresser as an external consultant and two patient representatives. In the first of two parts, we present the key statements on epidemiology and the recommendations for diagnosis. Data from Germany show a population-based prevalence of AA of 0.22% (95% CI 0.21-0.22) for 2016 and 0.21% (95% CI 0.20-0.22) for 2020. This means that 170,000 people in Germany were diagnosed with alopecia areata (AA) in 2020. International data show a pooled prevalence of 2.1%, but with large regional differences. Data on the incidence of AA from Germany show that 72 patients per 100,000 were newly diagnosed with AA in 2020 (RR 0.072%; 95% CI 0.07-0.08). Extrapolated to the German population, this means that around 70,000 people were newly diagnosed with AA in 2020.