Effective refractive error coverage in adults aged 50 years and older: estimates from population-based surveys in 61 countries.

BACKGROUND: In 2021, WHO Member States endorsed a global target of a 40-percentage-point increase in effective refractive error coverage (eREC; with a 6/12 visual acuity threshold) by 2030. This study models global and regional estimates of eREC as a baseline for the WHO initiative. METHODS: The Vision Loss Expert Group analysed data from 565 448 participants of 169 population-based eye surveys conducted since 2000 to calculate eREC (met need/[met need + undermet need + unmet need]). A binary logistic regression model was used to estimate eREC by Global Burden of Disease (GBD) Study super region among adults aged 50 years and older. FINDINGS: In 2021, distance eREC was 79·1% (95% CI 72·4-85·0) in the high-income super region; 62·1% (54·7-68·8) in north Africa and Middle East; 49·5% (45·0-54·0) in central Europe, eastern Europe, and central Asia; 40·0% (31·7-48·2) in southeast Asia, east Asia, and Oceania; 34·5% (29·4-40·0) in Latin America and the Caribbean; 9·0% (6·5-12·0) in south Asia; and 5·7% (3·1-9·0) in sub-Saharan Africa. eREC was higher in men and reduced with increasing age. Global distance eREC increased from 2000 to 2021 by 19·0%. Global near vision eREC for 2021 was 20·5% (95% CI 17·8-24·4). INTERPRETATION: Over the past 20 years, distance eREC has increased in each super region yet the WHO target will require substantial improvements in quantity and quality of refractive services in particular for near vision impairment. FUNDING: WHO, Sightsavers, The Fred Hollows Foundation, Fondation Thea, Brien Holden Vision Institute, Lions Clubs International Foundation.

The true cost of hidden waiting times for cataract surgery in Australia.

Cataract surgery is a safe, effective and common elective procedure in Australia but access is inequitable. True waiting times for cataract care are undisclosed or inconsistently reported by governments. Estimates of true waiting times range from 4 to 30 months and have been extended during the coronavirus disease 2019 (COVID-19) pandemic. Comparative analysis revealed that reducing waiting periods from 12 to 3 months would result in estimated public health system cost savings of $6.6 million by preventing 50 679 falls. Investment in public cataract services to address current unmet needs would prevent avoidable vision impairment and associated negative consequences.

Estimated number of ophthalmologists worldwide (International Council of Ophthalmology update): will we meet the needs?

BACKGROUND/AIMS: To estimate 2015 global ophthalmologist data and analyse their relationship to income groups, prevalence rates of blindness and visual impairment and gross domestic product (GDP) per capita. METHODS: Online surveys were emailed to presidents/chairpersons of national societies of ophthalmology and Ministry of Health representatives from all 194 countries to capture the number and density (per million population) of ophthalmologists, the number/density performing cataract surgery and refraction, and annual ophthalmologist population growth trends. Correlations between these data and income group, GDP per capita and prevalence rates of blindness and visual impairment were analysed. RESULTS: In 2015, there were an estimated 232 866 ophthalmologists in 194 countries. Income was positively associated with ophthalmologist density (a mean 3.7 per million population in low-income countries vs a mean 76.2 in high-income countries). Most countries reported positive growth (94/156; 60.3%). There was a weak, inverse correlation between the prevalence of blindness and the ophthalmologist density. There were weak, positive correlations between the density of ophthalmologists performing cataract surgery and GDP per capita and the prevalence of blindness, as well as between GDP per capita and the density of ophthalmologists doing refractions. CONCLUSIONS: Although the estimated global ophthalmologist workforce appears to be growing, the appropriate distribution of the eye care workforce and the development of comprehensive eye care delivery systems are needed to ensure that eye care needs are universally met.

Vision loss in Indigenous peoples of the world: a systematic review protocol.

REVIEW OBJECTIVE/QUESTION: The objectives of this review are.

Population-based assessment of visual acuity outcomes following cataract surgery in Australia: the National Eye Health Survey.

AIM: To assess the visual outcomes of cataract surgery among a national sample of non-Indigenous and Indigenous Australians. METHODS: This was a population-based study of 3098 non-Indigenous Australians (50-98 years) and 1738 Indigenous Australians (40-92 years), stratified by remoteness. A poor postoperative outcome in an eye that had undergone cataract surgery was defined as presenting distance visual acuity (PVA) <6/12-6/60, and a very poor outcome was defined as PVA <6/60. Effective cataract surgery coverage (eCSC; operated cataract and a good outcome (PVA ≥6/12) as a proportion of operable plus operated cataract) was calculated. RESULTS: The sampling weight adjusted cataract surgery prevalence was 19.8% (95% CI 17.9 to 22.0) in non-Indigenous Australians and 8.2% (95% CI 6.0 to 9.6) in Indigenous Australians. Among the non-Indigenous population, poor and very poor PVA outcomes were present in 18.1% and 1.9% of eyes, respectively. For Indigenous Australians, these values were 27.8% and 6.3%, respectively. The main causes of poor vision were refractive error (non-Indigenous=41.8%; Indigenous=41.9%) and coincident disease (non-Indigenous=43.3%; Indigenous=40.3%). The eCSC rates in the non-Indigenous and Indigenous populations were 88.5% (95% CI 85.2 to 91.2) and 51.6% (95% CI 42.4 to 60.7), respectively. CONCLUSION: Approximately half of eyes with a poor visual outcome postcataract surgery could be readily avoided through the appropriate refractive correction. The finding of a lower eCSC rate among Indigenous Australians suggests that improvements in access and quality of cataract services may be warranted in order to reduce cataract-related vision loss in the Indigenous population.

The prevalence of vision loss due to ocular trauma in the Australian National Eye Health Survey.

BACKGROUND: To determine the prevalence of vision loss due to ocular trauma in Australia. METHODS: The National Eye Health Survey (NEHS) is a population-based cross-sectional study that examined 3098 non-Indigenous Australians (aged 50-98 years) and 1738 Indigenous Australians (aged 40-92 years) living in 30 randomly selected sites, stratified by remoteness. An eye was considered to have vision loss due to trauma if the best-corrected visual acuity was worse than 6/12 and the main cause was attributed to ocular trauma. This determination was made by two independent ophthalmologists and any disagreements were adjudicated by a third senior ophthalmologist. RESULTS: The sampling weight adjusted prevalence of vision loss due to ocular trauma in non-Indigenous Australians aged 50 years and older and Indigenous Australians aged 40 years and over was 0.24% (95%CI: 0.10, 0.52) and 0.79% (95%CI: 0.56, 1.13), respectively. Trauma was attributed as an underlying cause of bilateral vision loss in one Indigenous participant, with all other cases being monocular. Males displayed a higher prevalence of vision loss from ocular trauma than females in both the non-Indigenous (0.47% vs. 1.25%, p=0.03) and Indigenous populations (0.12% vs. 0.38%, p=0.02). After multivariate adjustments, residing in Very Remote geographical areas was associated with higher odds of vision loss from ocular trauma. CONCLUSIONS: We estimate that 2.4 per 1000 non-Indigenous and 7.9 per 1000 Indigenous Australian adults have monocular vision loss due to a previous severe ocular trauma. Our findings indicate that males, Indigenous Australians and those residing in Very Remote communities may benefit from targeted health promotion to improve awareness of trauma prevention strategies.

Cataract surgery coverage rates for Indigenous and non-Indigenous Australians: the National Eye Health Survey.

OBJECTIVE: To determine cataract surgery coverage rates for Indigenous and non-Indigenous Australians. DESIGN: National cross-sectional population-based survey. SETTING: Thirty randomly selected Australian geographic sites, stratified by remoteness. PARTICIPANTS: 3098 non-Indigenous Australians aged 50 years or more and 1738 Indigenous Australians aged 40 years or more, recruited and examined in the National Eye Health Survey (NEHS) between March 2015 and April 2016. METHODS: Participants underwent an interviewer-administered questionnaire that collected socio-demographic information and past ocular care history, including cataract surgery. For those with visual acuity worse than 6/12, anterior segment photography and slit lamp examinations were conducted. MAIN OUTCOME MEASURES: Cataract surgery coverage rates according to WHO and NEHS definitions; associated risk factors. RESULTS: Cataract surgery coverage rates calculated with the NEHS definition 1 of vision impairment (visual acuity worse than 6/12) were lower for Indigenous than non-Indigenous participants (58.5% v 88.0%; odds ratio [OR], 0.32; P < 0.001). According to the World Health Organization definition (eligibility criterion: best-corrected visual acuity worse than 6/18), coverage rates were 92.5% and 98.9% for Indigenous and non-Indigenous Australians respectively. Greater age was significantly associated with higher cataract surgery coverage in Indigenous (OR, 1.41 per 10 years; P = 0.048) and non-Indigenous Australians (OR, 1.58 per 10 years; P = 0.004). CONCLUSIONS: The cataract surgery coverage rate was higher for non-Indigenous than Indigenous Australians, indicating the need to improve cataract surgery services for Indigenous Australians. The WHO definition of the coverage rate may overestimate the cataract surgery coverage rate in developed nations and should be applied with caution.

The Prevalence of Self-Reported Stroke in the Australian National Eye Health Survey.

BACKGROUND AND PURPOSE: The study aimed to determine the prevalence of and risk factors for self-reported stroke in Indigenous and non-Indigenous Australians. RESEARCH DESIGN AND METHODS: In this national eye study, 1738 Indigenous Australians (41.1% male) aged 40-92 years and 3098 non-Indigenous Australians (46.4% male) aged 50-98 years from 30 randomly selected sites, stratified by remoteness, were recruited and examined. Sociodemographic information and a history of stroke, diabetes, and ocular health were obtained using an interviewer-administered questionnaire. RESULTS: The crude prevalence of self-reported stroke was 5.04% (156 of 3098, 95% confidence interval: 4.29%-5.87%) for non-Indigenous Australians and 8.75% (152 of 1738, 95% confidence interval: 7.46%-10.17%) for Indigenous Australians (P < .0001). The age-adjusted prevalence of self-reported stroke for non-Indigenous and Indigenous Australians was 4.23% and 12.72%, respectively. The prevalence of stroke increased significantly with age for both Indigenous (odds ratio = 1.06 per year, P ≤ .001) and non-Indigenous Australians (odds ratio = 1.04 per year, P ≤ .001), with the Indigenous prevalence being higher than that of the non-Indigenous group at every age. CONCLUSIONS: The prevalence of self-reported stroke was 3 times higher in Indigenous Australians than in non-Indigenous Australians. This disparity is consistent with previous reports, highlighting the need for intensified prevention and support services to reduce the burden of stroke on Indigenous Australians.

Cataract Surgical Rate and Socioeconomics: A Global Study.

PURPOSE: Cataract is the leading cause of blindness and cataract surgical rate (CSR) is used as a proxy indicator of access to cataract services in a country. The aim of this study was to explore the associations between the CSR and the economic development of countries in terms of gross domestic product per capital (GDP/P) and gross national income per capita (GNI/P). METHODS: We systematically searched OVID (Medline and Embase), Pubmed, Embase.com, ISI Web of Science, and Cochrane Library databases, and retrieved additional data from unpublished reports. Cataract surgical rates and economic indicators (GDP/P, GNI/P) were collected for each country from 2005 to 2014. Complete data were used for the 50 largest countries according to World Health Organization (WHO) population estimates. Linear correlations between GDP/P and CSR were calculated. Cataract surgical rate data over two periods were used for analysis: 2005 to 2009 and 2010 to 2014 (CSR in 2009 or nearest year, CSR in 2014 or nearest year). RESULTS: Over the study period, CSR data were available for 152 countries across both time periods. Most of the CSR data were obtained from nongovernment organization (NGO) reports, including WHO reports. A good linear correlation between CSR and GDP/P was found overall, nearest to 2009 (ß = 0.162, Linear: y = 0.162x + 282.242; R2 = 0.665, P < 0.001). Regression analysis of CSR nearest to 2014 produced similar findings, with significant correlations between CSR and GDP/P (Linear: y = 0.208x + 94.008; R2 = 0.785, P < 0.001). When using GNI/P as an economic indicator, similarly excellent lines of fit were obtained. After adjusting for time and country, CSR was significantly associated with GDP/P (Coefficient = 0.147, R2 = 0.759, P < 0.001), and GNI/P (Coefficient = 0.152, R2 = 0.757, P < 0.001). Most countries had an increase in CSRs over time, with the greatest increases observed for Iran and Argentina. CONCLUSION: Cataract surgical rate and economic indicators are closely associated, indicating the strong influence of resource availability on healthcare delivery. Considering this relationship, it is important to be innovative in delivery of low-cost services and invest strategically in capacity development to meet cataract surgical need in low-resource settings.

Number of People Blind or Visually Impaired by Glaucoma Worldwide and in World Regions 1990 - 2010: A Meta-Analysis.

OBJECTIVE: To assess the number of individuals visually impaired or blind due to glaucoma and to examine regional differences and temporal changes in this parameter for the period from 1990 to 2012. METHODS: As part of the Global Burden of Diseases (GBD) Study 2010, we performed a systematic literature review for the period from 1980 to 2012. We primarily identified 14,908 relevant manuscripts, out of which 243 high-quality, population-based studies remained after review by an expert panel that involved application of selection criteria that dwelt on population representativeness and clarity of visual acuity methods used. Sixty-six specified the proportion attributable to glaucoma. The software tool DisMod-MR (Disease Modeling-Metaregression) of the GBD was used to calculate fraction of vision impairment due to glaucoma. RESULTS: In 2010, 2.1 million (95% Uncertainty Interval (UI):1.9,2.6) people were blind, and 4.2 (95% UI:3.7,5.8) million were visually impaired due to glaucoma. Glaucoma caused worldwide 6.6% (95% UI:5.9,7.9) of all blindness in 2010 and 2.2% (95% UI:2.0,2.8) of all moderate and severe visual impairment (MSVI). These figures were lower in regions with younger populations (<5% in South Asia) than in high-income regions with relatively old populations (>10%). From 1990 to 2010, the number of blind or visually impaired due to glaucoma increased by 0.8 million (95%UI:0.7, 1.1) or 62% and by 2.3 million (95%UI:2.1,3.5) or 83%, respectively. Percentage of global blindness caused by glaucoma increased between 1990 and 2010 from 4.4% (4.0,5.1) to 6.6%. Age-standardized prevalence of glaucoma related blindness and MSVI did not differ markedly between world regions nor between women. SIGNIFICANCE: By 2010, one out of 15 blind people was blind due to glaucoma, and one of 45 visually impaired people was visually impaired, highlighting the increasing global burden of glaucoma.

Global Estimates on the Number of People Blind or Visually Impaired by Diabetic Retinopathy: A Meta-analysis From 1990 to 2010.

OBJECTIVE: To estimate global and regional trends from 1990 to 2010 of the prevalence and number of persons visually impaired specifically by diabetic retinopathy (DR), as a complication of the precipitous trends in global diabetes, is fundamental for health planning purposes. RESEARCH DESIGN AND METHODS: The meta-analysis of published population studies from 1990 to 2012 for the Global Burden of Disease Study 2010 (GBD) yielded estimated global regional trends in DR among other causes of moderate and severe vision impairment (MSVI; presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60). RESULTS: Globally in 2010, out of overall 32.4 million blind and 191 million visually impaired people, 0.8 million were blind and 3.7 million were visually impaired because of DR, with an alarming increase of 27% and 64%, respectively, spanning the two decades from 1990 to 2010. DR accounted for 2.6% of all blindness in 2010 and 1.9% of all MSVI worldwide, increasing from 2.1% and 1.3%, respectively, in 1990. These figures were lower in regions with younger populations (<2% in East and Southeast Asia and Oceania) than in high-income regions (North America, Western Europe, and Australasia) with relatively aging populations (>4%). CONCLUSIONS: The number of persons with visual impairment due to DR worldwide is rising and represents an increasing proportion of all blindness/MSVI causes. Age-standardized prevalence of DR-related blindness/MSVI was higher in sub-Saharan Africa and South Asia. One out of 39 blind people had blindness due to DR, and 1 out of 52 visually impaired people had visual impairment due to DR.

Impact of diabetes on eye care service needs: the National Indigenous Eye Health Survey.

BACKGROUND: To assess the proportion of Australian Indigenous adults who require eye care services (separately among those with and without diabetes) and determine implications for eye care service planning. DESIGN: The National Indigenous Eye Health Survey (NIEHS) was a population-based study of 30 randomly selected geographical areas. PARTICIPANTS: The NIEHS included 1189 Indigenous adults aged 40-80 years. METHODS: A standardized eye examination was performed. MAIN OUTCOME MEASURE: The number requiring eye care services by diabetes status. RESULTS: Those with diabetes were older (median 53 years) than those without diabetes (median age 50 years), P < 0.001. The total estimated population-based need for annual eye care in the NIEHS population was 52% (n = 615), and of those 72% were people with diabetes. Among those with diabetes, 29% required further primary referral for diabetic retinopathy, 12% for cataract, 1% for trachomatous trichiasis and 5% for uncorrected distance refractive error. Among those without diabetes 13% required further primary referral for cataract, 0% for trachomatous trichiasis and 5% for uncorrected distance refractive error. CONCLUSION: This study has shown that among Indigenous adults, those with diabetes form 72% of those requiring an eye examination in any year. A key strategy to close the gap for vision for Australia's Indigenous population is to ensure those with diabetes undergo annual eye screening, have clearly defined care pathways and receive timely treatment. Establishing care pathways for those who have diabetes would also improve access to eye care services for others in the community.

Trachoma.

Trachoma is the most common infectious cause of blindness. Repeated episodes of infection with Chlamydia trachomatis in childhood lead to severe conjunctival inflammation, scarring, and potentially blinding inturned eyelashes (trichiasis or entropion) in later life. Trachoma occurs in resource-poor areas with inadequate hygiene, where children with unclean faces share infected ocular secretions. Much has been learnt about the epidemiology and pathophysiology of trachoma. Integrated control programmes are implementing the SAFE Strategy: surgery for trichiasis, mass distribution of antibiotics, promotion of facial cleanliness, and environmental improvement. This strategy has successfully eliminated trachoma in several countries and global efforts are underway to eliminate blinding trachoma worldwide by 2020.