Global, Regional, and National Epidemiology of Diabetic Nephropathy in Young Adults From 1990 to 2021

Background Diabetic nephropathy (DN) poses an escalating global health burden in young adults. This study assesses trends in DN incidence, mortality, and disability-adjusted life years (DALYs) among individuals aged 20–44 years from 1990 to 2021, and identifies risk factors for DN-related mortality. Methods This cross-sectional analysis utilized data from the Global Burden of Disease Study 2021, covering 204 countries and territories. Outcomes included morbidity, mortality, DALYs, and estimated annual percentage changes (EAPCs), stratified by region, country, age, sex, and socio-demographic index (SDI). Results Among 6,592,165 young adults (49.87% male), global DN cases rose by 75.00% (95% UI: −20.00–290.00%) from 1990 to 2021. Deaths increased by 54% (3,943 to 6,059), though mortality rates declined from 0.23 to 0.21 per 100,000. The Central SDI region had the highest incidence (2.72), mortality (0.279), and DALYs (18.23). Andean Latin America showed the steepest incidence rise (EAPC = 0.96). Nicaragua recorded the highest prevalence (8.91), while American Samoa had the highest mortality (2.62) and DALYs (141.99). Key mortality risk factors in 2021 included diets high in red meat, sodium, processed meat, sugar-sweetened beverages, and low in fruits, vegetables, or whole grains, alongside temperature extremes and lead exposure. Conclusions Despite declining mortality and DALY rates globally, absolute deaths and DALYs remain elevated, particularly in low-SDI regions. Enhanced epidemiological insights are critical for targeted prevention in young adults.