Global, regional, and national burden of seborrheic dermatitis in individuals aged 55 and older from 1990 to 2021: a trend analysis and future projections.

Seborrheic dermatitis (SD), an inflammatory dermatosis, significantly lowers quality of life, particularly in the elderly. Although studies have focused on the burden of SD globally before, trends among people 55 and older have received less attention. Utilizing the data released in 2021 by the Global Burden of Disease (GBD) consortium, our research was conducted to evaluate the global, regional, and national burden of SD in adults over 55 between 1990 and 2021 through incidence, prevalence, and disability-adjusted life years (DALYs) alongside advanced methods such as joinpoint regression analysis. We also performed decomposition analysis to examine the contributions of population and epidemiological changes. Correlation analysis was used to explore the assocaition between Socio-demographic Index (SDI) /climate-related parameters and SD. The global incidence of SD among adults aged 55 and older markedly rose from 1990 to 2021. The incidence grew by 120.84%, the prevalence by 125.09%, and the DALYs rose by 124.25%. Higher burdens were observed in the high and high-middle SDI regions, whereas low SDI areas displayed the highest age-standardized rates. Environmental factors, particularly global warming, were strongly connected with the incidence and prevalence of SD. Future projections suggested continued increases in SD cases through 2040. This study highlights the increasing burden of SD among older adults, emphasizing the role of demographic and environmental factors. Targeted public health interventions addressing aging populations and climate-related risks are urgent to mitigate the impact of SD globally.