Global trends in blindness with corneal opacity over the past 36 years are presented
The prevalence of blindness and visual impairment due to corneal opacities of various etiologies has been estimated. A decrease in the incidence of chlamydia etiology was noted.Researchers from the Universities of Baltimore, Sydney, Melbourne together with WHO experts studied the trends of blindness and visual impairment due to corneal opacity in adults depending on age, gender and region. Data from 1984 to 2020 were evaluated. The results of the study are published in the journal Ophthalmology.
They analyzed 36 years of data from patients aged 40 or more years worldwide with moderate to severe visual impairment or blindness on the background of corneal opacity of chlamydia and non-chlamydia etiology.
The global prevalence of nonchlamydia etiology in this cohort was 0.08%, and the incidence of severe visual impairment and blindness was 0.13%. A significant increase in incidence was observed with increasing age. The lowest incidence of blindness and moderate visual impairment was recorded in Latin America, Europe and Russia. In other regions this indicator was 2-8 times higher.
The global prevalence of blindness due to corneal opacity in chlamydia eye disease in patients aged 50 years and older was 0.009%. In this group, blindness occurred more frequently in females and also with increasing age. The worst situation was observed in African countries.
During the period studied, the global prevalence of blindness due to corneal opacity of chlamydia etiology decreased by 9%.
According to the latest estimates, 5.5 million people worldwide are blind in both eyes or have moderate visual impairment due to corneal opacity, and another 6.2 million are blind in one eye.
Experts believe that the decline in blindness rates for ocular chlamydia is due to the successful expansion of the global elimination program for this infectious disease and increased overall socioeconomic development. They emphasize the importance of timely detection and treatment of ocular chlamydia.