Abstract
BACKGROUND: Skin and subcutaneous diseases (SSDs) represent a growing global health burden. This study aims to assess global, regional and national trends in the incidence, prevalence, mortality and disability-adjusted life years (DALYs) associated with 15 specific SSDs from 1990 to 2021, providing a comprehensive stratification by age, sex, sociodemographic index (SDI) and region. METHODS: Data from the Global Burden of Disease (GBD) Study 2021, covering 204 countries, were analysed for age-standardized rates of incidence, prevalence, mortality and DALYs. Temporal trends were assessed using annual percentage change, age-period-cohort modelling and compositional analysis by SDI and GBD region. RESULTS: In 2021, SSDs accounted for 4.7 billion incident cases, 2.0 billion prevalent cases, 119 129 deaths and 41.9 million DALYs globally. Incidence and prevalence have increased by >35% since 1990, with a higher burden among females and older adults. Immune-mediated and inflammatory SSDs have overtaken infectious conditions in high- and middle-SDI regions, while infections still dominate in low-SDI regions. Sub-Saharan Africa and tropical Latin America had the highest incidence and mortality burdens, respectively. A marked epidemiological shift was observed across most regions, with notable compositional transitions in SSD types over time. CONCLUSIONS: SSDs are increasing globally, with significant regional and socio-economic disparities. Targeted interventions and improved access to dermatologic care are critical for addressing the growing burden, especially in resource-limited regions.