Global trends in cataract burden: a 30-year epidemiological analysis and prediction of 2050 from the Global Burden of Disease 2021 study

Background/aims Cataracts remain the leading cause of global blindness, particularly among ageing populations. This study evaluates the evolving burden of cataracts from 1990 to 2021, examines gender and socioeconomic disparities, assesses key risk factors and projects trends to 2050. Methods Data from the Global Burden of Disease 2021 database were systematically analysed across 204 countries, 21 regions and 5 sociodemographic index (SDI) levels. Indicators, including cataract prevalence, age-standardised prevalence rates, disability-adjusted life-years (DALYs) and age-standardised DALY rates (ASDR), were assessed. Decomposition analysis quantified the impacts of population growth, ageing and healthcare improvements, while Bayesian age-period-cohort models forecast trends to 2050. Joinpoint regression identified temporal trends, and health inequality metrics evaluated disparities. Risk factor contributions, such as air pollution, high BMI and metabolic risks, were also analysed. Results Global cataract prevalence increased significantly due to aging and population growth, while ASDR decreased, reflecting improved disease management. Disparities persist, with South Asia and sub-Saharan Africa bearing the highest burden due to limited surgical access, and females consistently exhibiting higher cataract burdens. Key contributors included air pollution and metabolic disorders, particularly in low-SDI regions. Predictions indicate a continued rise in global cataract cases and DALYs by 2050 under current demographic and epidemiological trends. Conclusions This study highlights persistent inequities in cataract burden and underscores the urgent need for tailored prevention, equitable surgical access and policies addressing ageing populations and modifiable risks to manage the rise in global cataract cases by 2050. Future policies should focus on improving surgical accessibility in low-SDI regions, enhancing chronic disease prevention and leveraging technological advancements for early detection and treatment.