Abstract
Purpose :
Over 300 million people worldwide suffer from visual impairment. Few quantitative measures exist to evaluate the impact of vision loss with most studies relying upon lost earnings. While hundreds of billions of US dollars per year are lost due to visual impairment, lost income occurs disproportionately in wealthy nations and may not therefore convey the impact of lost sight on lower income countries. As no suitable measures exist to compare the effect of vision loss across countries with disparate incomes, we propose a new method to estimate how many people around the world are driven into poverty by vision loss.
Methods :
National income distribution data (2019) were obtained from the United Nations and income-adjusted national poverty thresholds were obtained from the World Bank for all available countries. Country-level data for moderate visual impairment, severe visual impairment, and blindness were obtained from the Global Burden of Disease Study 2019. Moderate visual impairment was assumed to carry an 8.9% loss, severe visual impairment a 31.4% loss, and blindness a 33.8% loss of earnings. The relative number of inhabitants driven into poverty by vision loss were estimated by comparing income distribution data relative to the poverty threshold following adjustment for lost earnings from visual impairment.
Results :
Over four million people globally are driven into poverty as a result of vision loss. While the absolute number of lost dollars globally occurs predominately among high income nations, the impact of those lost dollars is disproportionately experienced by low-income countries (Figure 1). Among World Bank regions, East Asia, South Asia, and Sub-Saharan Africa account for 89% of all individuals driven into poverty despite making up less than half of the global population. Adjusting for population, vision loss continues to have an outsized impact on Sub-Saharan Africa (45% higher relative risk of poverty) compared to the remaining regions of the world.
Conclusions :
The risk of poverty due to vision loss is greatest in lower-income countries. The method described here may serve as a useful tool in advocacy, resource allocation, and in other fields beyond ophthalmology studying the impacts of disability and poverty.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.