Global, Regional, and National Epidemiology of Visual Impairment in Working-Age Individuals, 1990-2019

Jianqi Chen; Chunyan Yang; Weixin Zheng; Zhidong Li; Yanyi Huang; Shuyu Yao; Xuhao Chen; Xiaohong Chen; Rui Xie; Ruiyu Luo; Yuan Zhang; Guitong Ye; Xinyue Shen; Yue Xiao; Yingting Zhu; Wenmin Huang

doi:10.1001/jamaophthalmol.2023.5617

. 2023 Dec 7;142(1):25–32. doi: 10.1001/jamaophthalmol.2023.5617

Global, Regional, and National Epidemiology of Visual Impairment in Working-Age Individuals, 1990-2019

Jianqi Chen ¹, Chunyan Yang ¹, Weixin Zheng ¹, Zhidong Li ¹, Yanyi Huang ¹, Shuyu Yao ¹, Xuhao Chen ¹, Xiaohong Chen ¹, Rui Xie ¹, Ruiyu Luo ¹, Yuan Zhang ¹, Guitong Ye ¹, Xinyue Shen ¹, Yue Xiao ¹, Yingting Zhu ^1,^✉, Wenmin Huang ^1,^✉

¹State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China

Accepted for Publication: October 13, 2023.

Published Online: December 7, 2023. doi:10.1001/jamaophthalmol.2023.5617

^✉

Corresponding Authors: Yingting Zhu, MD, PhD (zhuyt35@mail.sysu.edu.cn) and Wenmin Huang, BD (huangwenmin@gzzoc.com), State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, 7 Jinsui Rd, Guangzhou 510623, China.

Author Contributions: Drs Zhu and W. Huang had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Drs J. Chen, Yang, and Zheng contributed equally to this work as co–first authors.

Concept and design: J. Chen, Yang, Xie, Zhang, Zhu, W. Huang.

Acquisition, analysis, or interpretation of data: J. Chen, Zheng, Li, Y. Huang, Yao, Xuhao Chen, Xiaohong Chen, Luo, Ye, Shen, Xiao.

Drafting of the manuscript: J. Chen, Yang, Zheng, Xie, Ye.

Critical review of the manuscript for important intellectual content: Li, Y. Huang, Yao, Xuhao Chen, Xiaohong Chen, Luo, Zhang, Shen, Xiao, Zhu, W. Huang.

Statistical analysis: J. Chen, Yao, Xuhao Chen, Xiaohong Chen, Xie, Luo, Zhang, Ye, Shen, Xiao.

Obtained funding: Zhang.

Administrative, technical, or material support: Yang, Zheng, Xiaohong Chen, Zhang, W. Huang.

Supervision: Zhu.

Conflict of Interest Disclosures: None reported.

Funding/Support: This work was supported by grants 2020YFA0112701 from the National Key Research and Development Project of China; 82171057 from the National Natural Science Foundation of China; 202206080005 from the Science and Technology Program of Guangzhou, China; 2022A1007 from the Major Science and Technology Project of Zhongshan City; and A2022301 from the Guangdong Provincial Medical Science and Technology Research Fund.

Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Data Sharing Statement: See Supplement 2.

Additional Contributions: The authors thank all the members of the Institute for Health Metrics and Evaluation, University of Washington, and all study groups involved in the Global Burden of Disease 2019 study.

^✉

Corresponding author.

PMCID: PMC10704345 PMID: 38060235

Key Points

Question

What was the burden of visual impairment in working-age individuals (aged 15-64 years) from 1990 to 2019?

Findings

In this cross-sectional study among working-age individuals from 204 countries and territories, there were 437 539 484 cases of visual impairment globally in 2019, representing a 91.46% increase in cases since 1990 and resulting in 12 563 276 disability-adjusted life-years. The burden increased in countries with a high and high-middle sociodemographic index, and the highest burden was seen in countries with a low sociodemographic index.

Meaning

The findings suggest that visual impairment is a major health issue in the global working-age population and that accurate estimation of its burden and trends is essential for developing strategies to address this growing health concern.

This cross-sectional study uses Global Burden of Disease data to investigate trends in visual impairment prevalence and disability-adjusted life-years among working-age people.

Abstract

Importance

Visual impairment in working-age individuals can affect their general health and employment prospects, leading to decreased social and economic productivity and increased poverty rates. Nonetheless, investigations in this population appear to be limited.

Objective

To investigate the trends of visual impairment prevalence and disability-adjusted life-years (DALYs) in working-age individuals from 1990 to 2019.

Design, Setting, and Participants

This cross-sectional, population-based study used data for individuals of working age (15-64 years) from 204 countries and territories obtained from the Global Burden of Disease 2019 study. The data analysis was performed between May 1 and 10, 2023.

Exposure

Visual impairment, defined as visual acuity of less than 6/18 (20/60) or near visual acuity of less than 6/12 (20/40) distance equivalent as determined by Snellen chart.

Main Outcomes and Measures

Trends of visual impairment prevalence, DALYs, and corresponding estimated annual percent changes (EAPCs) from 1990 to 2019 were stratified according to region, nation, and sociodemographic index (SDI).

Results

There were 437 539 484 (95% uncertainty interval [UI], 325 463 851-575 573 588) prevalent cases of visual impairment globally (53.12% female and 46.88% male) in 2019, representing an increase of 91.46% from 1990 (prevalent cases, 228 530 964; 95% UI, 172 515 833-297 118 596). Over 3 decades, visual impairment-associated DALYs increased from 7 601 852 (95% UI, 5 047 030-11 107 897) to 12 563 276 (95% UI, 8 278 866-18 961 723). Among the 5 SDI groups, the low-SDI group had the largest increase in DALYs (898 167 [95% UI, 597 161-1 301 931] in 1990 to 1 634 122 [95% UI, 1 079 102-2 444 381] in 2019). Regionally, the greatest increase in prevalence was observed in Eastern Europe (EAPC, 0.10; 95% CI, 0.02-0.19). Among all countries and territories, Nepal had the highest national prevalence of visual impairment per 100 000 population in 2019 (26 008.45; 95% UI, 19 987.35-32 482.09), while South Sudan had the highest DALY rate per 100 000 population (480.59; 95% UI, 316.06-697.06).

Conclusions and Relevance

Despite the mild decrease in visual impairment prevalence rates in less-developed countries, these findings suggest that the number of prevalent cases globally has increased substantially, with discernible unfavorable patterns in developed regions. The findings support the notion that visual impairment in working-age individuals is a growing global health challenge. A better understanding of its epidemiology may facilitate the development of appropriate measures for prevention and treatment from both medical and social perspectives.

Introduction

The inaugural global study on vision conducted by the World Health Organization in 2019 revealed that a minimum of 2.2 billion individuals worldwide have some form of visual impairment.¹ Visual impairment and compromised eye health have substantial, far-reaching consequences on individuals, their families, and society as a whole.² This effect is particularly pronounced among individuals of working age (15-64 years), as visual impairment may hamper their employment prospects and work productivity, leading to increased poverty rates.³ This economic detriment, in turn, is associated with adverse outcomes for both the social and psychological well-being of these individuals. Therefore, the preservation of optimal vision among working-age individuals can be regarded as a complex issue that has implications for the overall advancement of society.

Initiatives focused on enhancing ocular well-being and reducing visual impairment among the populace of working-age individuals have the potential to greatly contribute to the achievement of the United Nations Sustainable Development Goals.⁴ However, previous studies have primarily focused on populations that are considered vulnerable, such as children and older adults, while less attention has been given to individuals of working age. Previous studies based on the Global Burden of Disease (GBD) study⁵ have investigated the burden of vision loss across all ages and provided valuable information.^6,7 To our knowledge, the long-term global patterns of visual impairment prevalence among working-age individuals have not been documented to date.

Therefore, this study examines the patterns of visual impairment prevalence and associated disability-adjusted life-years (DALYs) among working-age individuals from the GBD study between 1990 and 2019. This analysis may serve as a catalyst for the advancement of current and development of novel prevention and treatment strategies aimed at alleviating the health hazards associated with visual impairment among working-age individuals, which may have substantial outcomes with regard to personal well-being and socioeconomic productivity.

Methods

Study Design and Data Collection

This cross-sectional, population-based study used data from the GBD 2019 study, which assessed disease burden and risk factors across 204 countries and territories from 1990 to 2019.⁵ The study was approved by the medical ethics committee of the Zhongshan Ophthalmic Center, Sun Yat-sen University, which waived the requirement for obtaining informed consent because the analyzed data are anonymized, aggregated, and publicly available. The study was conducted and reported in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline.

We used the Global Health Data Exchange tool developed by the GBD study to collect data, standardized disease definitions, and prevalence information pertaining to individuals with visual impairment between the ages of 15 and 64 years.⁸ Data pertaining to the burden of visual impairment are derived from surveys conducted in representative population-based research that measure visual acuity or draw information from other sources, including peer-reviewed publications and grey literature, as well as surveys containing unit record data. Exclusion criteria were applied to data that lacked visual acuity measures that could be converted to the Snellen scale or did not evaluate either presenting or best-corrected vision.⁵

Visual impairment was defined as visual acuity of less than 6/18 (20/60) as determined by a Snellen chart or near visual acuity of less than 6/12 (20/40) distance equivalent.⁸ The primary indicators used to characterize the burden of visual impairment were prevalence, DALYs, and their respective rates. The DALYs and years lived with disability are equivalent because visual impairment does not cause mortality within the framework of the GBD study. The GBD algorithm provides rates per 100 000 population, accompanied by 95% uncertainty intervals (UIs) for each rate.

To summarize the age distribution pertaining to the visual impairment prevalence among working-age individuals, data were categorized into 10 distinct age groups, each spanning a period of 5 years. Age-standardized prevalence rates (ASPRs) were determined based on the age-standardized population from the GBD 2019 study.

The temporal trends of the visual impairment burden were examined by calculating the estimated annual percent changes (EAPCs) and analyzed at global, regional, and national levels as well as according to age group, sex, and sociodemographic index (SDI). The SDI is a comprehensive indicator of social and economic factors that influence health outcomes in each location. Its value ranges from 0 to 1 and is determined by calculating the geometric mean of the total fertility rate among individuals younger than 25 years, the average number of years of education among those aged 15 years or older, and the lag-distributed income per capita. Higher values indicate a higher number of years of education, higher income per capita, and lower fertility rate.⁵ The SDI values were used to classify countries and territories into 5 quintiles, ie, high-, high-middle–, middle-, low-middle–, and low-SDI groups.

Statistical Analysis

Data were analyzed between May 1 and 10, 2023. The mean EAPCs were computed through linear regression, and their corresponding 95% CIs were determined using linear modeling. When the upper limits of the EAPC 95% CIs are negative, a declining trend is indicated in the corresponding rate. Conversely, when the lower limits of the EAPC 95% CIs are positive, an increasing trend is suggested.⁹ The association between disease burden and the SDI was analyzed using Pearson correlation analysis and locally estimated scatterplot smoothing. All analyses were performed using RStudio, version 4.2.2 (Posit Software). All P values were 2-sided, but P values were not adjusted for multiple analyses.

Results

Global Trends

Among working-age individuals, there were 437 539 484 (95% UI, 325 463 851-575 573 588) prevalent cases of visual impairment in 2019 (53.12% female and 46.88% male), which is a 91.46% increase relative to the number of prevalent cases in this population in 1990 (228 530 964; 95% UI, 172 515 833-297 118 596). The corresponding ASPR changed accordingly from 8034.44 per 100 000 population (95% UI, 6048.03-10 464.58) in 1990 to 8287.82 per 100 000 population (95% UI, 6170.51-10 898.50) in 2019, with an EAPC of −0.04 (95% CI, −0.09 to 0.01) (Table).

Table. Prevalence of Visual Impairment Among Working-Age Individuals Globally and by Sociodemographic Index Level, 1990-2019.

Location	1990		2019		1990-2019 EAPC (95% CI)
Location	Prevalent cases (95% UI)	ASPR per 100 000 (95% UI)	Prevalent cases (95% UI)	ASPR per 100 000 (95% UI)	1990-2019 EAPC (95% CI)
Global	228 530 964 (172 515 833 to 297 118 596)	8034.44 (6048.03 to 10 464.58)	437 539 484 (325 463 851 to 575 573 588)	8287.82 (6170.51 to 10 898.50)	−0.04 (−0.09 to 0.01)
SDI level
High	14 208 682 (11 163 104 to 17 830 704)	2511.56 (1972.62 to 3150.71)	21 201 298 (16 655 909 to 26 591 907)	2714.80 (2136.60 to 3397.78)	0.28 (0.23 to 0.32)
High-middle	48 341 239 (36 030 753 to 63 797 757)	6596.70 (4908.95 to 8713.68)	87 850 344 (64 918 600 to 116 745 108)	7234.51 (5362.55 to 9591.98)	0.17 (0.10 to 0.24)
Middle	71 210 621 (53 394 749 to 93 223 065)	8598.88 (6418.49 to 11 293.75)	150 517 609 (111 519 507 to 198 362 723)	8598.81 (6383.21 to 11 323.38)	−0.17 (−0.24 to −0.10)
Low-middle	66 991 962 (50 429 381 to 87 462 608)	13 738.84 (10 323.84 to 17 961.44)	121 278 951 (89 561 768 to 160 340 720)	12 175.99 (8990.51 to 16 096.32)	−0.53 (−0.58 to −0.48)
Low	27 685 066 (20 970 396 to 35 729 371)	14 147.49 (10 704.30 to 18 258.12)	56 516 614 (42 304 596 to 73 707 024)	13 118.21 (9811.32 to 17 080.13)	−0.36 (−0.43 to −0.30)

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Abbreviations: ASPR, age-standardized prevalence rate; EAPC, estimated annual percent change; SDI, sociodemographic index; UI, uncertainty interval.

The observed increase in the number of prevalent cases of visual impairment during the study period was seen in all age groups, with the largest increase (114.38%) documented in the 45-to-49-year group and the smallest (17.43%) in the 15-to-19-year group. In terms of sex distribution, in 2019, the number of prevalent cases was generally higher in females than in males. The female to male visual impairment prevalence ratio generally increased with age and peaked among individuals aged 55 to 59 years (Figure 1A and B).

Figure 1. — DALY indicates disability-adjusted life-year.

The global number of DALYs attributed to visual impairment in working-age individuals increased by 65.27% during the study period from 7 601 852 (95% UI, 5 047 030-11 107 897) in 1990 to 12 563 276 (95% UI, 8 278 866-18 961 723) in 2019. However, the corresponding DALY rate decreased from 261.74 per 100 000 population (95% UI, 173.75-383.10) in 1990 to 239.60 per 100 000 population (95% UI, 157.89-361.24) in 2019, with an EAPC of −0.38 (95% CI, −0.42 to −0.35) (eTable 1 in Supplement 1).

From 1990 to 2019, the number of visual impairment–associated DALYs increased for all age groups, with the largest increase (85.47%) observed among individuals aged 50 to 54 years. In both 1990 and 2019, the highest number of visual impairment–associated DALYs was recorded among individuals aged 60 to 64 years (1 635 467 and 2 871 194, respectively). In 2019, DALY rates were higher in females than in males in all age groups, and the lowest rate was observed among individuals aged 15 to 19 years for both sexes (Figure 1C and D).

SDI-Based Trends

The highest number of prevalent cases of visual impairment among working-age individuals in 2019 was documented in the middle-SDI group (150 517 609; 95% UI, 111 519 507-198 362 723), which also exhibited the largest increase in this number during the study period (111.37%). Notably, the high- and high-middle–SDI groups had the largest increases in visual impairment ASPR among working-age individuals (high SDI: EAPC, 0.28 [95% CI, 0.23-0.32]; high-middle SDI: EAPC, 0.17 [95% CI, 0.10-0.24]) (Table; Figure 2A).

Figure 2. — ASPR indicates age-standardized prevalence rate; DALY, disability-adjusted life-year; SDI, sociodemographic index.

In 2019, the middle-SDI group had the highest number of visual impairment–associated DALYs (4 462 630; 95% UI, 2 949 219-6 683 325), with a dramatic increase of 79.64% from 1990 (2 484 194; 95% UI, 1 657 845-3 601 932). However, the largest increase (81.94%) in this number was recorded in the low-SDI group (898 167 [95% UI, 597 161-1 301 931] in 1990 to 1 634 122 [95% UI, 1 079 102-2 444 381] in 2019). Nonetheless, most SDI groups experienced declining trends in DALYs, with the most substantial decline observed in the low-middle–SDI group (EAPC, −0.98; 95% CI, −1.02 to −0.94) (eTable 1 in Supplement 1; Figure 2B). In terms of specific causes of visual impairment, the middle-, low-middle–, and low-SDI groups consistently exhibited a higher disease burden, while the increasing trends observed in high- and high-middle–SDI groups primarily reflect the increasing trends in cataracts, diabetic retinopathy, near vision loss, and age-related macular degeneration (eTables 2 and 3 in Supplement 1).

Geographic Regional Trends

In 2019, among 21 geographic regions, South Asia had the highest number of prevalent cases of visual impairment (160 978 294; 95% UI, 119 058 263-212 907 590), whereas Australasia had the lowest (428 401; 95% UI, 336 141-536 224) among working-age individuals. Regionally, the greatest increase in prevalence was observed in Eastern Europe (EAPC, 0.10; 95% CI, 0.02-0.19). In 2019, the highest ASPR was recorded in southern sub-Saharan Africa (17 276.83; 95% UI, 12 013.11-23 854.99; SDI, 0.64), while the lowest was in the high-income Asia Pacific (1848.94; 95% UI, 1470.92-2286.88; SDI, 0.87). Between 1990 and 2019, most regions experienced a decline in the ASPR of visual impairment (eTable 4 in Supplement 1). The ASPR was higher than the mean global rate (8287.82 per 100 000 population) in 5 regions (central sub-Saharan Africa, eastern sub-Saharan Africa, western sub-Saharan Africa, South Asia, and southern sub-Saharan Africa) and lower in 16 regions (Figure 2C).

In 2019, the highest number of visual impairment–associated DALYs among working-age individuals was documented in South Asia (4 307 943; 95% UI, 2 818 330-6 588 225), whereas the lowest was documented in Oceania (16 488; 95% UI, 10 800-24 459). South Asia (SDI, 0.54) had the highest DALY rate (417.29; 95% UI, 273.26-638.81), and high-income North America (SDI, 0.86) had the lowest (78.45; 95% UI, 51.52-114.98). However, from 1990 to 2019, South Asia showed the largest decrease in visual impairment–associated DALY rates (EAPC, −1.06; 95% CI, −1.11 to −1.00). In 2019, 8 regions (eg, South Asia) had higher and 13 regions (eg, high-income North America) had lower DALY rates than the mean global rate (239.60 per 100 000 population) (eTable 1 in Supplement 1; Figure 2D).

National Trends

Among 204 countries, in 2019, India had the highest number of prevalent cases of visual impairment among working-age individuals (132 016 555; 95% UI, 96 913 772-175 978 448), while Nepal had the highest ASPR (26 008.45; 95% UI, 19 987.35-32 482.09) (eTable 5 and eFigure 1A in Supplement 1). The largest ASPR increase during the study period was recorded in the Russian Federation (EAPC, 0.15; 95% CI, 0.02-0.27), whereas the largest decrease in was Equatorial Guinea (EAPC, −1.19; 95% CI, −1.25 to −1.14) (eTable 5 and eFigure 1B in Supplement 1; Figure 3A). In 2019, the highest and lowest ASPRs of visual impairment were observed in Nepal (SDI, 0.42) and Sweden (SDI, 0.87), respectively. The ASPRs were higher than the mean global ASPR (8287.82 per 100 000 population) for 2019 in 53 countries and lower in 151 countries.

Figure 3. — DALY indicates disability-adjusted life-year.

The highest number of visual impairment–associated DALYs among working-age individuals in 2019 was documented in India (3 487 003; 95% UI, 2 280 822-5 343 289), while South Sudan had the highest DALY rate per 100 000 population (480.59; 95% UI, 316.06-697.06) (eTable 6 and eFigure 1C in Supplement 1). Equatorial Guinea (EAPC, −2.36; 95% CI, −2.48 to −2.24) had the largest DALY rate decrease (eTable 6 and eFigure 1D in Supplement 1; Figure 3B). While South Sudan (SDI, 0.36) had the highest rate of visual impairment–associated DALYs, Sweden (SDI, 0.87) had the lowest. The DALY rates were higher than the mean global rate for 2019 (239.60) in 61 countries and lower than this rate in 143 countries. Both visual impairment ASPRs and associated DALYs showed a negative correlation with the SDI (r = −0.69 and −0.75, respectively; both P < .001) (eFigure 2 in Supplement 1).

Discussion

The findings of this cross-sectional study show a consistent increasing trend in the number of prevalent cases of visual impairment among working-age individuals globally. From 1990 to 2019, this number has increased by a striking 91.46%. This increase in the burden of visual impairment was observed in all age groups. Additionally, we found negative correlations between the SDI and visual impairment burden.

Because of its association with general health and employment prospects, visual impairment in working-age individuals has gradually become a major public health problem. As this study offers valuable insights into the disease burden in this population in various regions and countries with diverse development levels, it could assist policy makers and clinicians in formulating suitable strategies for visual impairment prevention and treatment.

The SDI-based differences in visual impairment prevalence and associated DALYs observed in this study might be associated with the lack of available resources and knowledge to prevent and treat eye diseases in less-developed countries and territories. The disease burden for most causes of visual impairment has been consistently higher in the low-, low-middle–, and middle-SDI groups and may be associated with the combination of sociodemographic disadvantages and insufficient eye health systems. Namely, these countries have been reported to have a higher prevalence of visual impairment while also experiencing a scarcity of ophthalmologists.^10,11 For instance, less-developed countries exhibit a greater burden of cataracts while having lower surgical coverage despite cataracts being the primary cause of preventable blindness.¹² Fortunately, these countries have achieved progress in reducing the visual impairment prevalence among working-age individuals. This achievement can be attributed to their rapid development as well as the implementation of the Vision 2020 and Universal Eye Health programs over the past few decades. Regarding the high- and high-middle–SDI groups, the escalating prevalence of cataracts, diabetic retinopathy, near vision loss, and age-related macular degeneration might be attributed to the aging of the working-age population. With the continuing aging of the population globally, this issue is expected to worsen in the future.

From an economic perspective, the achievement of sustainable development is contingent on economic productivity across the individual, familial, and national domains. Labor force decline caused by unemployment or underemployment diminishes the overall capacity of an economy to produce goods and services.¹³ As prior research has established, a correlation exists between impaired visual acuity and unemployment.¹⁴ According to the US Bureau of Labor Statistics, a mere 29% of working-age individuals in the US with visual impairment are employed.¹⁵ In a previous study, the employment rate among a sample of US residents seeking visual rehabilitative services was only 18%.¹⁴ Hence, the substantial burden of visual impairment in underdeveloped areas may lead to sustained poverty and exacerbate enduring disparities and inequalities in development.

Given the anticipated benefits to general health and development, it is necessary to reduce the burden and address the outcomes of visual impairment in working-age individuals. From a global perspective, it is essential to establish strategies for maintaining healthy vision among individuals as they age, particularly in higher-SDI groups. The effectiveness of these strategies could be crucial for achieving the goals set forth in the United Nations Sustainable Development Goals and the Decade of Healthy Aging (2020-2030),¹⁶ which necessitate collaborative efforts to tackle the increasing prevalence of visual impairment and to advocate for healthy aging. Controlling the prevalence of diabetes mellitus is a crucial concern given its well-established association with vascular dysfunction and consequent role as an important contributor to visual impairment.¹⁷ Regarding the lower-SDI groups, these findings underscore the importance of implementing proportionate universalism and fostering sustained international cooperation, both of which entail the establishment of multiple health system building blocks while placing particular emphasis on enhancing the capacity of underdeveloped regions in terms of eye health services.^2,18

For instance, cataracts and uncorrected refractive errors, the most common causes of moderate and severe visual impairment as well as blindness, can be effectively treated. To increase workforce participation and productivity gains, expanding access to treatment for these conditions should be a global priority. Individuals whose vision cannot be restored should receive vision rehabilitation services and workplace adaptations to enable them to remain in the workforce. Potential policies could encompass incentive programs aimed at recruiting individuals for providing assistance to people with visual impairment; initiatives to modify work environments to accommodate their needs; and efforts to ensure equal and unbiased access to comprehensive employment opportunities, promotions, and career advancement strategies. Moreover, it is probable that individuals residing in high-income countries and those with a higher socioeconomic status in all nations possess the means to avail themselves of cutting-edge technologies and visual aids that facilitate their engagement in the workforce. By ensuring equitable employment opportunities and favorable working conditions for individuals with visual impairment, both governmental bodies and private enterprises can contribute to the eradication of poverty, mitigation of social disparities, enhancement of health outcomes, promotion of well-being, and augmentation of economic productivity, thus alleviating the burden of this public health concern.

Limitations

This study has some limitations. First, our analysis was based on the GBD database. Although GBD methodologies are widely recognized for their advanced nature, robustness, and dependability, their effectiveness is inherently limited by the quality of the available data. In addition, for specific countries characterized by limited data availability, the GBD study used mathematical modeling techniques to derive estimates, which has inevitably led to bias in the estimates.

Conclusions

The results of this cross-sectional study indicate that the global burden of visual impairment among working-age individuals has been progressively increasing over the past 3 decades and is anticipated to persistently grow in the foreseeable future. This increase can be attributed to the increase in the working-age population during that 30-year period. Our results indicate a decrease in the ASPRs of visual impairment in less-developed countries; however, the number of prevalent cases has actually increased remarkably, indicating a substantial burden in these countries. Moreover, we identified discernible unfavorable patterns in the ASPR trend in developed regions. The correlation between visual impairment in working-age individuals and their personal well-being and socioeconomic productivity necessitates further research and prompts development of efficient strategies aimed at alleviating the burden of visual impairment.

Supplement 1.

eFigure 1. Prevalence Rates and Corresponding EAPCs, DALY Rates and Corresponding EAPCS of Visual Impairment in Working-Age Individuals in 204 Countries and Territories

eFigure 2. Correlation of Age-Standardized Prevalence and DALY Rates With the Sociodemographic Index in 2019

eTable 1. DALYs of Visual Impairment in Working-Age Individuals Between 1990 and 2019 at the Global Level, by Sociodemographic Index Subcategory, and at the Regional Level

eTable 2. Prevalence of Visual Impairment in Working-Age Individuals Between 1990 and 2019 by Cause and Sociodemographic Index Subcategory

eTable 3. DALYs of Visual Impairment in Working-Age Individuals Between 1990 and 2019 by Cause and Sociodemographic Index Subcategory

eTable 4. Prevalence of Visual Impairment in Working-Age Individuals Between 1990 and 2019 at the Regional Level

eTable 5. Prevalence of Visual Impairment in Working-Age Individuals Between 1990 and 2019 at the National Level

eTable 6. DALYs of Visual Impairment in Working-Age Individuals Between 1990 and 2019 at the National Level

Click here for additional data file.^{(1.2MB, pdf)}

Supplement 2.

Data Sharing Statement

Click here for additional data file.^{(16.6KB, pdf)}

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