Prevalence and secular trends of four causes of blindness and visual impairment in Iran (1990–2019): a comparative study based on the Global Burden of Disease project's data.

Purpose: The purpose of this study was to investigate the prevalence of cataracts, refractive disorders, age-related macular disease (AMD), and glaucoma, as well as their trends from 1990 to 2019 in Iran, in comparison with high-middle socio-demographic index (HMSDI) countries and the world, using the Global Burden of Disease (GBD) 2019 study. Methods: The GBD study provided data on the prevalence of blindness and visual impairment (VI), as well as four of their causes including cataracts, refractive disorders, age-related macular disease (AMD), and glaucoma. Using Joinpoint analysis, the annual percent change (APC) was calculated to assess the trend of change in prevalence in each category of diseases from 1990 to 2019, stratified by sex and age, for Iran, HMSDI countries, and the world. Results: In 2019, refractive errors and cataracts were the most common causes of blindness and VI for both genders in Iran, HMSDI countries and the world. Iran had a higher age-standardized prevalence in all four categories of ophthalmologic disorders compared to HMSDI countries and the world for both genders in 2019. Additionally, the age-specific prevalence of all four disorders in 2019 was higher in Iran compared to HMSDI countries. However, in terms of trends of prevalence from 1990 to 2019, the rate of reduction for the four ophthalmologic disorders in Iran was higher than in HMSDI and the world for both males and females. Furthermore, Iran had a greater percentage of reduction in prevalence for all age groups in all four disorders compared to HMSDI countries. Conclusion: The prevalence of cataracts, refractive errors, AMD, and glaucoma in Iran was higher compared to HMSDI countries in 2019 for both sexes and all age groups, but the trends of prevalence for all four disorders from 1990 to 2019 in Iran had a higher slope of reduction compared to HMSDI countries for all ages and sexes. [ABSTRACT FROM AUTHOR]