Prevalence of Blindness and Visual Impairment due to Cataract   Among Adults in the Southern Urals (according to a Population-Based Study)

Aim. To study the prevalence of blindness and visual impairment due to cataract among adults aged 40 years and older. Material and methods. In 2015–2017 a cross-sectional population-based Ural Eye and Medical Study (UEMS) was conducted at Ufa Eye Research Institute, Ufa, Russia. Results. Cataracts were the most common cause of moderate and severe visual impairment among adults of the Southern Urals aged 40 years and older (n=109; 59.9%; 95% CI: 52.7–67.1). The most frequent types of cataract observed were nuclear-cortical cataract(n=53; 29.1%), cortical (n=29; 15.9%) and nuclear cataract(n=24; 13.2%); less frequently posterior subcapsular cataract (n=1; 0.5%), mature (n=1; 0.5%) and secondary cataract (n=1; 0.5%). Cataract caused blindness in 3 cases (27.3%; 95% CI: 19.6–35.7). Conclusions. Cataracts were the leading cause of moderate and severe visual impairment among people of the Southern Urals aged 40 years and older, cataract-induced blindness was estimated at 27.3% of all cases (95% CI: 19.6–35.7). The analysis suggests that the need for cataract surgery remains high in the population. Key words: population-based study, visual impairment, blindness, cataract