Abstract
Purpose :
There are limited reports on the incidence of visual impairment (VI) in Asia, home to more than half of the world’s population. This meta-analysis aimed to estimate annual incidences of low vision (LV) and blindness in Asia.
Methods :
Systematic review and meta-analysis were conducted. Published articles on incidence of VI in Asia adults, were systematically searched from PubMed, Embase, Web-of-science, and Scopus. Random effects meta-analysis with logit transformation was performed to pool incidence rates of best-corrected and presenting LV and blindness. Following WHO standard (based on better-seeing eye), LV was defined as visual acuity >20/60 at baseline, <20/60-20/400 at follow-up; blindness was defined as visual acuity >20/400 at baseline, <20/400 at follow-up. Overall incidence was calculated using the weighted population distribution of Asia, based on the United Nations’ World Population Prospects 2019. Incidence projection of VI in 2021-2030 was modelled by performing the Binomial-Normal Hierarchical Model fitted with Markov Chain Monte Carlo simulations.
Results :
12 Asian population-based cohort studies were included for meta-analysis. In Asia, for people aged ≥30 years, the overall annual incidences were 0.40% (95%CI, 0.34-0.47%) for presenting LV, 0.02% (0.02-0.03%) for presenting blindness; 0.03% (0.02-0.04%) for best-corrected LV, 0.02% (0.018-0.022%) for best-corrected blindness. By age groups, annual incidences for presenting LV were 0.19% for 30-39 years, 0.37% for 40-49 years, 0.41% for 50-59 years, and 1.06% for ≥60 years. On the other hand, for these 4 groups, annual incidences for best-corrected LV were 0.01%, 0.02%, 0.06%, and 0.13%, respectively. Overall, there were higher annual incidences for best-corrected and presenting VI in rural areas compared to urban, and in females compared to males (all P<0.001). Taking into account these estimated incidence rates, the burden of presenting LV was projected to increase by 121.6 million (95% CI, 62.8-213.3 million) from year 2021-2030, and by 11.8 million (95% CI, 3.9-29.7 million) for presenting blindness.
Conclusions :
In Asia, incidence of VI increases with age with higher rates in females and those living in rural area. In the next decade, the burden of presenting VI in Asia is projected to increase by 134.4 million. Estimates from our study can help guide future regional eye health policies and prevention programs.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.