# Global, regional, and national burden of alopecia areata in adolescents and young adults aged 10–24 years from 1990 to 2021: a trend analysis

## TL;DR

This study analyzed the global burden of alopecia areata in adolescents and young adults from 1990 to 2021, finding increasing cases but decreasing age-standardized rates with notable regional and gender differences.

## Contribution

The study provides the first comprehensive trend analysis of alopecia areata burden in 10–24-year-olds using GBD 2021 data across 204 countries.

## Key findings

- Global age-standardized rates of alopecia areata decreased from 1990 to 2021, with the most significant decline in high socioeconomic index regions.
- Females had a higher burden of alopecia areata than males, but both groups showed a decline, with males experiencing a more significant reduction.
- North America had the highest burden, while South Asia, Western Europe, and the Middle East showed increasing trends.

## Abstract

Alopecia areata (AA) is a common autoimmune hair loss disorder, posing a significant threat to the mental health and quality of life of patients, especially adolescents and young adults at critical stages of psychological and social development. This study conducted a comprehensive comparative analysis of the burden of AA in the global population aged 10–24 years, providing scientific basis for the prevention and treatment of AA.

Using data from GBD 2021, AA prevalence, incidence, and disability-adjusted life years (DALYs) for individuals aged 10–24 years in 204 countries and territories from 1990 to 2021 were analyzed by age, sex, and region. Temporal trends were evaluated by average annual percentage of change (AAPC) calculated by the Joinpoint regression model.

From 1990 to 2021, the number of prevalence cases, incidence cases, and DALYs of AA among individuals aged 10–24 worldwide increased, however, the corresponding age-standardized rates all decreased, with AAPCs of −0.1374 (95% CI: −0.1396 to −0.1354), −0.1404 (95% CI: −0.1425 to −0.1387), and −0.1351 (95% CI: −0.1382 to −0.1317), respectively. The burden of AA in females was higher than that in males, and both decreased, with a more significant decrease in males; the 20–24 group had the largest rate decline but remained most burdened; the burden in high socioeconomic indices (SDI) regions was the highest, but the decrease was the most significant; the burden in North America was the highest, while the burden in South Asia, Western Europe, and North Africa and the Middle East regions showed an upward trend; the burden in the United States was the highest, but the decline was the greatest, and the increase was the largest in the United Arab Emirates.

The absolute burden of AA among adolescents and young adults worldwide was still increasing, but the age-standardized rates had slightly decreased. There were significant age, gender, regional, and socioeconomic inequalities in the burden distribution. These differences should be fully considered, and comprehensive prevention, treatment, and psychological support measures should be adopted to continuously monitor and formulate precise strategies for AA in adolescents and young adults, reducing its burden and profound psychological impact.