Global, regional and national burden of major blindness-associated ophthalmologic conditions, 1990-2021, with forecasts to 2050: a systematic analysis for the Global Burden of Disease Study 2021.

Abstract

The global burden of blindness and vision loss continues to increase, yet comprehensive analyses of underlying causes remain limited. This study estimated the global and regional burden of blindness-related diseases from 1990 to 2021 and projected trends to 2050 to inform public health strategies. We analysed data from the Global Burden of Disease Study (GBD) 2021 to estimate the prevalence and disability-adjusted life years (DALYs) rates of blindness and vision loss, focusing on six major causes, including glaucoma, cataract, age-related macular degeneration, refraction disorders, near vision loss and other vision loss. We quantified the contribution of risk factors, and future trends were projected to 2050 using GBD's forecast framework. In 2021, the global age-standardised prevalence and DALY rates of blindness were 15 784.3 (95% uncertainty interval (UI), 12 761.4-19 502.3) and 342.8 (224.2-503.6) per 100 000. Although global age-standardised DALY rates remained statistically stable between 1990 and 2021, regional trends varied numerically. Southern sub-Saharan Africa recorded the highest age-standardised prevalence rate in 2021 at 16 741.4 (13 187.8-21 129.5), whereas the highest DALY rate was observed in South Asia at 497.1 (345.3-691.6). While the overall burden of blindness did not differ significantly by sex, glaucoma showed a higher burden in males. From 1990 to 2021, cataract DALY rates attributable to household air pollution decreased by 38.4%, with projections showing stable age-standardised rates through 2050. As populations age, the global burden of vision loss is projected to grow, with particularly high impact in lower-sociodemographic index regions such as Southern Sub-Saharan Africa and South Asia.