Trends in Prevalence of Blindness and Distance and Near Vision Impairment Over 30 Years and Contribution to the Global Burden of Disease in 2020

Background: The Vision Loss Expert Group and Global Burden of Disease Study have extensively updated estimates of global vision loss burden in 2020, temporal changeover 3 decades and forecasts for 2050.Methods: A systematic review and meta-analysis was conducted of population-based datasets relevant to vision impairment (VI) from January 1980 to October 2018. Hierarchical models were fitted to estimate 2020 prevalence (with 95% uncertainty intervals, UI) of (1) mild VI (presenting visual acuity [PVA]< 6/12 to 6/18), moderate to severe VI (MSVI; PVA< 6/18 to 3/60), blindness (PVA< 3/60); and (2) VI from uncorrected presbyopia (presenting near vision distance visual acuity> 6/12).Findings: In 2020, an estimated 43.2 million (95% UI: 37.5-48.2 million; 55% female) people were blind, 295.3 (95% UI 267.0-325.5) million had MSVI, 257.3 (95% UI 232.2-284.7) million had mild VI, and 507.4 million (95% UI 369.3–663.8) were VI from uncorrected presbyopia. Globally among adults aged≥ 50 years, age-standardised prevalence of blindness reduced by 29% between 1990 and 2020, while MSVI increased slightly (+ 2.4%). The number of blind people increased by 50.2% and MSVI by 91.6%. By 2050, we predict 895.5 million people blind/VI.Interpretation: It is encouraging that age-adjusted prevalence of blindness has reduced over the past 3 decades, yet due to population growth progress is not keeping pace with needs. We face enormous challenges in avoiding vision impairment as the global population grows and ages.