Global, regional and national burden of skin and subcutaneous diseases: a systematic analysis of the Global Burden of Disease Study 2021

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.