Global economic productivity losses from vision impairment and blindness

Global estimates on the number of people blind or visually impaired by diabetic retinopathy: a meta-analysis from 2000 to 2020

OBJECTIVES

To estimate global and regional trends from 2000 to 2020 of the number of persons visually impaired by diabetic retinopathy and their proportion of the total number of vision-impaired individuals.

METHODS

Data from population-based studies on eye diseases between 1980 to 2018 were compiled. Meta-regression models were performed to estimate the prevalence of blindness (presenting visual acuity <3/60) and moderate or severe vision impairment (MSVI; <6/18 to ≥3/60) attributed to DR. The estimates, with 95% uncertainty intervals [UIs], were stratified by age, sex, year, and region.

RESULTS

In 2020, 1.07 million (95% UI: 0.76, 1.51) people were blind due to DR, with nearly 3.28 million (95% UI: 2.41, 4.34) experiencing MSVI. The GBD super-regions with the highest percentage of all DR-related blindness and MSVI were Latin America and the Caribbean (6.95% [95% UI: 5.08, 9.51]) and North Africa and the Middle East (2.12% [95% UI: 1.55, 2.79]), respectively. Between 2000 and 2020, changes in DR-related blindness and MSVI were greater among females than males, predominantly in the super-regions of South Asia (blindness) and Southeast Asia, East Asia, and Oceania (MSVI).

CONCLUSIONS

Given the rapid global rise in diabetes and increased life expectancy, DR is anticipated to persist as a significant public health challenge. The findings emphasise the need for gender-specific interventions and region-specific DR healthcare policies to mitigate disparities and prevent avoidable blindness. This study contributes to the expanding body of literature on the burden of DR, highlighting the need for increased global attention and investment in this research area.

The Sleep Health of Individuals with Visual Impairments: A Scoping Review

PURPOSE

Amidst the global aging population and an increasing prevalence of visual impairment across all age groups, this study aims to investigate the current state of research on sleep health in visually impaired populations.

METHODS

A scoping review was conducted to synthesize the existing literature on sleep health and visual impairment. We employed conceptual mapping to identify key research topics, analyzing data from four databases: PubMed (n = 290), CINAHL (n = 81), Scopus (n = 117), and PsycInfo (n = 96). A total of 83 peer-reviewed articles, published from 1977 to August 2023, were included in the review.

RESULTS

Our analysis identified 11 distinct eye health conditions including blindness, glaucoma, diabetic retinopathy, low vision, cataract, retinitis pigmentosa, macular degeneration, optic neuropathy, visual field defects, ocular hypertension, and retinal vein occlusion. Additionally, 8 major sleep problems were recognized: abnormal sleep duration, daytime sleepiness, insomnia, Non-24-Hour Sleep Wake Disorder, sleep apnea, sleep disorders, sleep disturbances, and sleep disordered breathing. The dominant research themes were (1) poor sleep quality in individuals with visual impairments and ophthalmic diseases, (2) high prevalence of sleep issues in patients with ophthalmic diseases, (3) sleep apnea in patients with ophthalmic conditions, and (4) circadian rhythm disruptions in blind individuals.

CONCLUSION

This review highlights research gaps that, when addressed, could greatly enhance our comprehension of the interplay between visual impairment and sleep health. Bridging these gaps promises to lead to more holistic care strategies, potentially improving vision functioning and rehabilitation outcomes for individuals with visual impairments.

The Risk of Cardiovascular Disease Risk Among Adults with Vision Impairment from Low-, Middle- and High-Income Countries

PURPOSE

The limited evidence for cardiovascular disease (CVD) among adults with vision impairment (VI) has often been from developed countries using self-reported VI. This study evaluated the association of objectively-determined VI with the risk of CVD among adults from low-, middle-, and high-income countries.

METHODS

Data were from 32,268 adults aged 30-74 years without CVD or blindness from China, Ghana, India, Mexico, Russian Federation, South Africa, and the United States during 2007-2010. VI and severe VI was defined as presenting visual acuity worse than 6/18, and 6/60, respectively. The Framingham risk algorithm was used to estimate the risk for incident CVD. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals.

RESULTS

The mean age of participants was 46.4 years, with half of them being women (49.3%). The age-adjusted prevalence of VI ranged from 1.1% (United States) to 14.2% (South Africa) while severe VI ranged from 0.4% (United States) to 4.5% (Ghana). In models adjusting for country, sociodemographic factors, waist girth, healthcare use, activities of daily living and other health-related factors, VI was associated with CVD risk ≥ 10% (OR = 1.69, 95% CI: 1.22-2.36). This observed association was largely consistent across countries (p = 0.119). The observed CVD risk was similar among adults with moderate or severe VI (OR = 0.95, 95% CI: 0.50-1.83). CVD risk was higher among adults with VI who were <65 years old (OR = 1.89, 95% CI: 1.36-2.63) or were employed (OR = 2.24, 95% CI: 1.58-3.16).

CONLUSIONS

This cross-national study shows that individuals with VI are at high risk for future CVD.

Anti-vascular endothelial growth factor biosimilars for neovascular age-related macular degeneration

RATIONALE

Neovascular age-related macular degeneration (AMD) is a progressive eye disease characterized by choroidal neovascularization (CNV) and is a leading cause of vision loss and disability worldwide. Although intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy is an effective treatment option that helps to prevent vision loss or to improve visual acuity in people with neovascular AMD, treatment imposes a significant financial burden on patients and healthcare systems. A biosimilar is a biological product that has been developed to be nearly identical to a previously approved biological product. The use of biosimilars may help reduce costs and so may increase patient access to effective biologic medicines with similar levels of safety to the drugs on which they are based.

OBJECTIVES

To assess the benefits and harms of anti-VEGF biosimilar agents compared with their corresponding anti-VEGF agents (i.e. the reference products) that have obtained regulatory approval for intravitreal injections in people with neovascular AMD.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, two other databases, and two trials registries together with reference checking and contact with study authors to identify studies that are included in the review. The latest search date was 2 June 2023.

ELIGIBILITY CRITERIA

We included randomized controlled trials (RCTs) that compared approved anti-VEGF biosimilars with their reference products for treating the eyes of adult participants (≥ 50 years) who had an active primary or recurrent choroidal neovascularization lesion secondary to neovascular AMD.

OUTCOMES

Our outcomes were: best-corrected visual acuity (BCVA), central subfield thickness (CST), vision-related quality of life, serious ocular and non-ocular adverse events (AE), treatment-emergent adverse events (TEAEs), anti-drug antibodies (ADAs), and serum concentrations of biosimilars and reference drugs.

RISK OF BIAS

We assessed the risk of bias (RoB) for seven outcomes reported in a summary of findings table by using the Cochrane RoB 2 tool.

SYNTHESIS METHODS

We synthesized results for each outcome using meta-analysis, where possible, by calculating risk ratios (RR) and mean differences (MD) with 95% confidence intervals (CI) for dichotomous outcomes and continuous outcomes, respectively. Where this was not possible due to the nature of the data, we summarized the results narratively. We used GRADE to assess the certainty of evidence for prespecified outcomes.

INCLUDED STUDIES

We included nine parallel-group multi-center RCTs that enrolled a total of 3814 participants (3814 participating eyes), with sample sizes that ranged from 160 to 705 participants per study. The mean age of the participants in these studies ranged from 67 to 76 years, and the proportion of women ranged from 26.5% to 58.7%. Ranibizumab (Lucentis) was the reference product in seven studies, and aflibercept (Eyelea) was the reference product in two others. All the included studies had been supported by industry. The follow-up periods ranged from 12 to 52 weeks (median 48 weeks). Five studies (56%) were conducted in multi-country settings across Europe, North America and Asia, two studies in India, and one each in Japan and the Republic of Korea. We judged all the included studies to have met high methodological standards.

SYNTHESIS OF RESULTS

With regard to efficacy, our meta-analyses demonstrated that anti-VEGF biosimilars for neovascular AMD resulted in little to no difference compared with the reference products for BCVA change at 8 to 12 weeks (MD -0.55 Early Treatment Diabetic Retinopathy Study (ETDRS) letters, 95% CI -1.17 to 0.07; 8 studies, 3603 participants; high-certainty evidence) and the proportion of participants who lost fewer than 15 letters in BCVA at 24 to 48 weeks (RR 0.99, 95% CI 0.98 to 1.01; 7 studies, 2658 participants; moderate-certainty evidence). Almost all participants (96.6% in the biosimilar group and 97.0% in the reference product group) lost fewer than 15 letters in BCVA. The evidence from two studies suggested that there was no evidence of difference between biosimilars and reference products in vision-related quality of life measured by the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) summary scores at 24 to 48 weeks (MD 0.82, 95% CI -0.70 to 2.35; 2 studies, 894 participants; moderate-certainty evidence). With regard to the safety profile, meta-analyses also revealed little to no difference between anti-VEGF biosimilars and the reference products for the proportion of participants who experienced serious ocular AEs (RR 1.24, 95% CI 0.68 to 2.26; 7 studies, 3292 participants; moderate-certainty evidence), and for TEAEs leading to investigational product discontinuation or death (RR 0.96, 95% CI 0.63 to 1.46; 8 studies, 3497 participants; moderate-certainty evidence). Overall, 1.4% of participants in the biosimilar group and 1.2% in the reference product group experienced serious ocular adverse events. The most frequently documented serious ocular AEs were retinal hemorrhage and endophthalmitis. Although the evidence is of low certainty due to imprecision, meta-analysis suggested that anti-VEGF biosimilars led to no difference compared with the reference products for cumulative incidence of ADAs (RR 0.84, 95% CI 0.58 to 1.22; 8 studies, 3066 participants; low-certainty evidence) or mean maximum serum concentrations (MD 0.42 ng/mL, 95% CI -0.22 to 1.05; subgroup of 3 studies, 100 participants; low-certainty evidence). We judged the overall risk of bias to be low for all studies.

AUTHORS' CONCLUSIONS

In our review, low to high certainty evidence suggests that there is little to no difference, to date, between the anti-VEGF biosimilars approved for treating neovascular AMD and their reference products in terms of benefits and harms. While anti-VEGF biosimilars may be a viable alternative to reference products, current evidence for their use is based on a limited number of studies - particularly for comparison with aflibercept - with sparse long-term safety data, and infrequent assessment of quality of life outcomes. Our effect estimates and conclusions may be modified once findings have been reported from studies that are currently ongoing, and studies of biosimilar agents that are currently in development.

FUNDING

Cochrane Eyes and Vision US Project is supported by grant UG1EY020522, National Eye Institute, National Institutes of Health. Takeshi Hasegawa and Hisashi Noma were supported by Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science (Grant numbers: 22H03554, 19K03092, 24K06239).

REGISTRATION

Protocol available via doi.org/10.1002/14651858.CD015804.

Predictors and consequences of visual trajectories in Chinese older population: A growth mixture model

Background

Given the relatively high prevalence of vision impairment and the heterogeneity of visual changes among the elderly population, we aimed to identify the visual trajectories and to examine the predictors and consequences associated with each trajectory class.

Methods

We analysed data from 2235 participants involved in the 5th, 6th, 7th, and 8th waves of the Chinese Longitudinal Healthy Longevity Survey (CLHLS), where vision impairment was evaluated using an adapted Landolt-C chart during each wave. We employed a growth mixture model (GMM) to identify distinct visual trajectories and logistic regression analysis to examine the predictors associated with each trajectory class. Furthermore, we investigated the effect of visual trajectories on distal consequences, including cognitive function, activities of daily living (ADL), instrumental activities of daily living (IADL), depression, anxiety, and fall risk. Within the CLHLS study, cognitive function was assessed using the Chinese version of the Mini-Mental State Examination (CMMSE), ADL via the Katz index, and IADL through a modified version of Lawton's scale. Lastly, depression was assessed using the 10-item version of the Centre for Epidemiologic Studies (CES-D-10), while anxiety was measured using the Generalized Anxiety Disorder scale (GAD-7). Fall risk was determined by asking the question: 'Have you experienced any falls within the past year?'

Results

We identified two distinct visual trajectories in our analysis. Most older adults (n = 1830, 81.9%) initially had a good vision level that diminished ('high-baseline decline' group). Conversely, the remaining participants (n = 405, 18.1%) initially had a lower vision level that improved over time ('low-baseline improvement' group). The 'high-baseline decline' group was more likely to include older adults with relatively higher body mass index (BMI) (odds ratio (OR) = 1.086; 95% confidence interval (CI) = 1.046, 1.127), individuals with higher formal educational qualifications (OR = 1.411; 95% CI = 1.068, 1.864), those current engaging in exercise (OR = 1.376; 95% CI = 1.046, 1.811), and individuals reporting more frequent consumption of fruit (OR = 1.357; 95% CI = 1.053, 1.749). Conversely, the 'low-baseline improvement' group had a higher likelihood of including older individuals (OR = 0.947; 95% CI = 0.934, 0.961), residents of nursing homes (OR = 0.340; 95% CI = 0.116, 0.993) and those self-reporting cataracts (OR = 0.268; 95% CI = 0.183, 0.391) and glaucoma (OR = 0.157; 95% CI = 0.079, 0.315). Furthermore, the 'high-baseline decline' group showed a positive impact on distal consequences, adjusting for sex, birthplace, residence, main occupation, education, economic status, and marital status. This impact included cognitive function (correlation coefficient (β) = 2.092; 95% CI = 1.272, 2.912), ADL (β  = -0.362; 95% CI = -0.615, -0.108), IADL (β  = -1.712; 95% CI = -2.304, -1.121), and reported lower levels of depression (β  = 0.649; 95% CI = 0.013, 1.285). We observed no significant influence on fall risk and anxiety within the identified visual trajectories in the adjusted model.

Conclusions

Vision in older adults with ocular disease could potentially be improved. Having formal education, maintaining an appropriate BMI, engaging in exercise, and consuming fruit more frequently appear to be beneficial for the visual health of the elderly. Considering the negative impact of visual impairment experience on distal cognition, self-care ability, and depression symptoms, stakeholder should prioritise long-term monitoring and management of vision impairment among older adults.

Visual impairment, employment status, and reduction in income: the Canadian Longitudinal Study on Aging

OBJECTIVE

To examine the employment status of those with and without visual impairment and eye disease and to examine the association between visual impairment and eye disease and a reduction in income over a 3-year period.

DESIGN

Population-based prospective cohort study.

PARTICIPANTS

A total of 12,174 nonretired participants aged 45-64 years old in the Canadian Longitudinal Study on Aging.

METHODS

Visual impairment was defined if binocular presenting or pinhole-corrected monocular visual acuity in the better eye was worse than 20/40 at baseline. Self-reported diagnoses of age-related macular degeneration (AMD) and glaucoma were collected. Employment status (employed, not employed due to sickness or disability, or unemployed) was based on questions on labour force participation. Income reduction was defined as household income <$50,000 per year at follow-up when household income was ≥$50,000 at baseline. Multinomial and logistic regressions were used to adjust for demographic and health variables.

RESULTS

Visual impairment using binocular presenting visual acuity (odds ratio [OR] = 2.09; 95% CI, 1.21-3.62) and pinhole-corrected visual acuity (OR = 2.99; 95% CI, 1.54-5.83) were associated with a higher odds of not being employed due to sickness or disability after adjustment. AMD (OR = 1.82; 95% CI, 1.11-3.01) and glaucoma (OR = 2.05; 95% CI, 1.28-3.28) at baseline were both associated with reductions in income over a 3-year period after adjustment.

CONCLUSION

Individuals with visual impairment experienced lower employment, and those with AMD or glaucoma were more likely to have their incomes decline over 3 years. Policies to improve workplace participation by those with vision loss are needed.

The effects of selected neglected tropical diseases on economic performance at the macrolevel in Africa

BACKGROUND

Neglected tropical diseases (NTDs) such as leprosy, lymphatic filariasis (LF), schistosomiasis and onchocerciasis are endemic in several African countries. These diseases can lead to severe pain and permanent disability, which can negatively affect the economic productivity of the affected person(s), and hence resulting into low economic performance at the macrolevel. Nonetheless, empirical evidence of the effects of these NTDs on economic performance at the macrolevel is sparse. This study therefore investigates the effects of the above-mentioned NTDs on economic performance at the macrolevel in Africa.

METHODS

The study employs a panel design with data comprising 24 to 45 African countries depending on the NTD in question, over the period, 2002 to 2019. Gross domestic product (GDP) is used as the proxy for economic performance (Dependent variable) and the prevalence of the above-mentioned NTDs are used as the main independent variables. The random effects (RE), fixed effects (FE) and the instrumental variable fixed effects (IVFE) panel data regressions are used as estimation techniques.

RESULTS

We find that, an increase in the prevalence of the selected NTDs is associated with a fall in economic performance in the selected African countries, irrespective of the estimation technique used. Specifically, using the IVFE regression estimates, we find that a percentage increase in the prevalence of leprosy, LF, schistosomiasis and onchocerciasis is associated with a reduction in economic performance by 0.43%, 0.24%, 0.28% and 0.36% respectively, at either 1% or 5% level of significance.

CONCLUSION

The findings highlight the need to increase attention and bolster integrated efforts or measures towards tackling these diseases in order to curb their deleterious effects on economic performance. Such measures can include effective mass drug administration (MDA), enhancing access to basic drinking water and sanitation among others.

The effects of age-related macular degeneration on work productivity: A meta-analysis

Age-related macular degeneration (AMD) is one of the leading causes of vision loss and blindness in older adults. Given the aging population in developed countries and the increased participation of older adults in the labour market, this paper aims to understand the impact of AMD on workplace productivity. Economic studies, comparative studies, observational studies, cohort studies, case series, randomized control trials, clinical trials, multicenter studies from MEDLINE, EMBASE, and CINHAL, as well as grey literature, were systematically searched to obtain all relevant literature. Duplicate records were removed, and two independent reviewers screened records for relevance. After screening, a risk of bias assessment was carried out. Data were extracted and a meta-analysis was performed using STATA 15.0. Fixed-effect and random-effect models were computed based on heterogeneity. Seven studies consisting of 3,060,864 subjects from 5 different countries were included in this systematic review. Mean wages lost due to impaired work productivity ranged from $1,395 to $55,180. The mean unemployment rate attributed to AMD ranged from 5.50% to 77.00%. Meta-analysis results indicated a significant unemployment rate (SMD = 0.44, CI: [0.27, 0.62]). Patients with AMD experience impaired work productivity as demonstrated by the wages lost and significantly higher rates of unemployment.

Service Quality and Residents' Preferences for Facilitated Self-Service Fundus Disease Screening: Cross-Sectional Study

BACKGROUND

Fundus photography is the most important examination in eye disease screening. A facilitated self-service eye screening pattern based on the fully automatic fundus camera was developed in 2022 in Shanghai, China; it may help solve the problem of insufficient human resources in primary health care institutions. However, the service quality and residents' preference for this new pattern are unclear.

OBJECTIVE

This study aimed to compare the service quality and residents' preferences between facilitated self-service eye screening and traditional manual screening and to explore the relationships between the screening service's quality and residents' preferences.

METHODS

We conducted a cross-sectional study in Shanghai, China. Residents who underwent facilitated self-service fundus disease screening at one of the screening sites were assigned to the exposure group; those who were screened with a traditional fundus camera operated by an optometrist at an adjacent site comprised the control group. The primary outcome was the screening service quality, including effectiveness (image quality and screening efficiency), physiological discomfort, safety, convenience, and trustworthiness. The secondary outcome was the participants' preferences. Differences in service quality and the participants' preferences between the 2 groups were compared using chi-square tests separately. Subgroup analyses for exploring the relationships between the screening service's quality and residents' preference were conducted using generalized logit models.

RESULTS

A total of 358 residents enrolled; among them, 176 (49.16%) were included in the exposure group and the remaining 182 (50.84%) in the control group. Residents' basic characteristics were balanced between the 2 groups. There was no significant difference in service quality between the 2 groups (image quality pass rate: P=.79; average screening time: P=.57; no physiological discomfort rate: P=.92; safety rate: P=.78; convenience rate: P=.95; trustworthiness rate: P=.20). However, the proportion of participants who were willing to use the same technology for their next screening was significantly lower in the exposure group than in the control group (P<.001). Subgroup analyses suggest that distrust in the facilitated self-service eye screening might increase the probability of refusal to undergo screening (P=.02).

CONCLUSIONS

This study confirms that the facilitated self-service fundus disease screening pattern could achieve good service quality. However, it was difficult to reverse residents' preferences for manual screening in a short period, especially when the original manual service was already excellent. Therefore, the digital transformation of health care must be cautious. We suggest that attention be paid to the residents' individual needs. More efficient man-machine collaboration and personalized health management solutions based on large language models are both needed.

COUNTY-LEVEL ANALYSIS OF EYE EXAM ACCESS AND UTILIZATION IN THE UNITED STATES

PURPOSE

The eye exam is a critical tool for the prevention, screening, and diagnosis of ocular and systemic conditions. In this study, we characterize county-level variation in eye exam access and utilization for Medicare patients in the United States.

METHODS

This nationwide study uses the Medicare Physician & Other Practitioners - by Provider and Service dataset. We included all ophthalmologists and optometrists who performed eye exams on Medicare beneficiaries within a United States county in 2019. For every county where exams were performed, we calculated the number of practicing vision testing providers, percentage of providers classified as ophthalmologists, and the number of exams per 100 Medicare beneficiaries. Multiple linear regression was used to characterize associations between these variables and county characteristics, including measures of poverty, education, and income.

RESULTS

In 2019, 28937,540 eye exams were performed by 46,000 providers in 2,291 U.S. counties. In the median county, 34.9 eye exams were provided per 100 Medicare beneficiaries. The average county had 20.1 exam providers, 16.5% of whom were ophthalmologists. There were a median 6.6 eye exam providers for every 10,000 Medicare beneficiaries in the average county. The average provider performed 517.8 exams. Regression showed counties with lower median household incomes, higher poverty rates, or fewer high-school graduates had fewer eye exam providers per 10,000 Medicare beneficiaries and fewer eye exams performed per 100 Medicare beneficiaries.

CONCLUSIONS

We find significant county-level variation in eye exam utilization and provider availability. This reflects broader, well-recognized trends in socioeconomic health disparities in the U.S.

Racial Disparities in Glaucoma Vision Outcomes and Eye Care Utilization: An IRIS Registry Analysis

PURPOSE

To evaluate racial disparities in vision outcomes and eye care utilization among glaucoma patients.

DESIGN

Retrospective cohort study.

METHODS

In this population-based IRIS Registry (Intelligent Research in Sight) study, we included patients with minimum one diagnosis code for glaucoma at least 6 months prior to January 1, 2015 and at least one eye exam, visual field (VF), optical coherence tomography (OCT), or eye-related inpatient or emergency department (ED) code in 2015. Multivariable logistic and negative binomial regression models were used to assess vision and utilization outcomes, respectively, across race and ethnicity from January 1, 2015 to January 1, 2020. Vision outcomes included cup-to-disc ratio (CDR) progression > 0.80, poor vision (visual acuity 20/200 or worse), low vision codes, and need for glaucoma filtering surgery. Utilization outcomes included outpatient eye exams, OCTs, VFs, inpatient/ED encounters, and lasers/surgeries.

RESULTS

Among 996,297 patients, 73% were non-Hispanic White, 15% non-Hispanic Black, 9% Hispanic, 3% Asian/Pacific Islander, and 0.3% Native American/Alaska Native. Compared to White eyes, Black and Hispanic eyes had higher adjusted odds of CDR progression (odds ratio [OR] = 1.12, 95% confidence interval [CI] = 1.08-1.17; OR = 1.28, 95% CI = 1.22-1.34), poor vision (OR = 1.26, 95% CI = 1.22-1.29; OR = 1.26, 95% CI = 1.22-1.31), glaucoma filtering surgery (rate ratio (RR) = 1.47, 95% CI = 1.42-1.51; RR = 1.13, 95% CI = 1.09-1.18). Hispanic eyes also had increased odds of low vision diagnoses (Hispanic OR = 1.18, 95% CI = 1.07-1.30). Black and Hispanic patients were less likely to have eye exams (RR = 0.94, 95% CI = 0.94-0.95; RR = 0.99, 95% CI = 0.99-0.99) and OCTs (RR = 0.86, 95% CI = 0.85-0.86; RR = 0.97, 95% CI = 0.96-0.98), yet Black patients had higher odds of inpatient/ED encounters (RR = 1.64, 95% CI = 1.37-1.96) compared to White patients. Native American patients were more likely to have poor vision (OR = 1.17, 95% CI = 1.01-1.36) and less likely to have outpatient visits (RR = 0.89, 95% CI = 0.86-0.91), OCTs (RR = 0.85, 95% CI = 0.82-0.89), visual fields (RR = 0.91, 95% CI = 0.88-0.94) or lasers/surgeries (RR = 0.87, 95% CI = 0.79-0.96) compared to White patients.

CONCLUSIONS

We found that significant disparities in US eye care exist with Black, Hispanic, and Native American patients having worse vision outcomes and less disease monitoring. Glaucoma may be undertreated in these racial and ethnic minority groups, increasing risk for glaucoma-related vision loss.

Estimation of the lost productivity to the GDP and the national cost of correcting visual impairment from refractive error in Kenya

BACKGROUND

In developing countries such as Kenya, minimal attention has been directed towards population based studies on uncorrected refractive error (URE). However, the absence of population based studies, warrants utilization of other avenues to showcase to the stakeholders in eye health the worth of addressing URE. Hence this study estimated the lost productivity to the Gross Domestic Product (GDP) as a result of URE and the national cost required to address visual impairment from URE in Kenya.

METHODS

The lost productivity to the GDP for the population aged 16-60 years was calculated. Thereafter the productivity loss of the caregivers of severe visual impaired individuals was computed as a product of the average annual productivity for each caregiver and a 5% productivity loss due to visual impairment. The productivity benefit of correcting refractive error was estimated based on the minimum wage for individuals aged between 16-60 years with URE. Estimation of the national cost of addressing URE was based on spectacle provision cost, cost of training functional clinical refractionists and the cost of establishing vision centres. A cost benefit analysis was undertaken based on the national cost estimates and a factor of 3.5 times.

RESULTS

The estimated lost productivity to the GDP due to URE in in Kenya is approximately US$ 671,455,575 -US$ 1,044,486,450 annually for population aged between 16-60 years. The productivity loss of caregivers for the severe visually impaired is approximately US$ 13,882,899 annually. Approximately US$ 246,750,000 is required to provide corrective devices, US$ 413,280- US$ 108,262,300 to train clinical refractionists and US$ 39,800,000 to establish vision centres. The productivity benefit of correcting visual impairment is approximately US$ 41,126,400 annually. Finally, a cost benefit analysis showed a return of US$ 378,918,050 for human resources, US$ 863,625,000 for corrective devices and US$ 139,300,000 for establishment of vision centres.

CONCLUSION

The magnitude of productivity loss due to URE in Kenya is significant warranting prioritization of refractive error services by the government and all stakeholders since any investment directed towards addressing URE has the potential to contribute a positive return.

Blindness and visual impairment: quality of life and accessibility in the city of Turin

Purpose

Despite the increase in socio-health conditions and, in general, the focus on health worldwide, many diseases still adversely affect the quality of life (QoL), including those causing vision loss. The main purpose of this study was to evaluate the QoL of people with visual impairments through a questionnaire and identify issues concerning everyday life in the urban and extra-urban areas of Turin.

Patients and methods

A personalized questionnaire including 25 questions was distributed to 100 enrolled patients. It was designed by integrating the most widely used questionnaires related to the QoL of people with visual impairment with questions concerning the city of Turin. The inclusion criteria were any degree of visual impairment (from mild defect to complete blindness), according to Law n. 138/2001 classification. The exclusion criteria were mental disability and residence in care homes. Finally, statistical analysis was performed. Pearson's Chi-Square test was used to evaluate the strength of the association between two qualitative variables in different sections of the questionnaire. The results were classified as statistically significant with a p-value of ≤0.05 or borderline (0.05 < p-value<0.10).

Results

Based on responses to question 7 (Q7), 67% of selected patients stated that sight markedly influences their QoL. Moreover, 49% of patients responding to question 12 considered themselves almost completely dependent on other people regarding mobility and movement in and around Turin. In total, 57% used public transport (Q13); however, 50% of them found it challenging to access (Q14). Personal aids (e.g., white cane and magnifying glasses) were adopted only by 51% (Q15), and 63% of patients responding to question 18 suggested a refinement of urban aids (e.g., road signs). Of the 53 patients, 30 patients (56.6%) considered Turin a livable city for visually impaired people (Q19); however, 44 patients (84.6%) reported no significant improvements in Turin's urban logistics during the last 5 years and highlighted the urgent need to improve urban aids (Q21). Furthermore, the statistical associations studied showed that the loss of vision plays a significant role in influencing the perception of one's QoL (association of questions 7 and 8, X2 = 112.119, Cramer's V = 0.548, p-value <0.001). In addition, it is more difficult for visually impaired patients living outside the city to move outdoors (Chi-Square = 10.637, Cramer's V = 0.326, p - 245 value = 0.031) and to cross the street (Chi-Square = 14.102, Cramer's V = 0.376, p-250 value = 0.007). Finally, those who feel independent perceive their lives to be more fulfilling (Chi-Square = 268, X2 = 37.433; Cramer's V = 0.306, p value = 0.002).

Conclusion

Our study showed how vision loss plays a remarkable role in influencing the perception of one's QoL. Furthermore, it highlighted how the implementation of mobility and the use of personal aids for living in a city, such as Turin, were associated with a better perception of QoL by visually impaired patients. However, it is necessary to improve urban technological development according to the needs of people with visual disability.

Cost-of-illness studies of inherited retinal diseases: a systematic review

BACKGROUND

While health care and societal costs are routinely modelled for most diseases, there is a paucity of comprehensive data and cost-of-illness (COI) studies for inherited retinal diseases (IRDs). This lack of data can lead to underfunding or misallocation of resources. A comprehensive understanding of the COI of IRDs would assist governmental and healthcare leaders in determining optimal resource allocation, prioritizing funding for research, treatment, and support services for these patients.

METHODS

Following PRISMA guidelines, a literature search was conducted using Medline, EMBASE and Cochrane databases, from database inception up to 30 Jun 2023, to identify COI studies related to IRD. Original studies in English, primarily including patients with IRDs, and whose main study objective was the estimation of the costs of IRDs and had sufficiently detailed methodology to assess study quality were eligible for inclusion. To enable comparison across countries and studies, all annual costs were standardized to US dollars, adjusted for inflation to reflect their current value and recalculated on a "per patient" basis wherever possible. The review protocol was registered in PROSPERO (registration number CRD42023452986).

RESULTS

A total of nine studies were included in the final stage of systematic review and they consistently demonstrated a significant disease burden associated with IRDs. In Singapore, the mean total cost per patient was roughly US$6926/year. In Japan, the mean total cost per patient was US$20,833/year. In the UK, the mean total cost per patient with IRD ranged from US$21,658 to US$36,549/year. In contrast, in the US, the mean total per-patient costs for IRDs ranged from about US$33,017 to US$186,051 per year. In Canada, these mean total per-patient costs varied between US$16,470 and US$275,045/year. Non-health costs constituted the overwhelming majority of costs as compared to healthcare costs; 87-98% of the total costs were due to non-health costs, which could be attributed to diminished quality of life, poverty, and increased informal caregiving needs for affected individuals.

CONCLUSION

IRDs impose a disproportionate societal burden outside health systems. It is vital for continued funding into IRD research, and governments should incorporate societal costs in the evaluation of cost-effectiveness for forthcoming IRD interventions, including genomic testing and targeted therapies.

Persistence of severe global inequalities in the burden of blindness and vision loss from 1990 to 2019: findings from the Global Burden of Disease Study 2019

AIMS

To assess the global burden and economic inequalities in the distribution of blindness and vision loss between 1990 and 2019.

METHODS

A secondary analysis of the Global Burden of Diseases, Injuries and Risk Factors Study (GBD) 2019. Data for disability-adjusted life-years (DALYs) due to blindness and vision loss were extracted from the GBD 2019. Data for gross domestic product per capita were extracted from the World Bank database. Slope index of inequality (SII) and concentration index were computed to assess absolute and relative cross-national health inequality, respectively.

RESULTS

Countries with high, high-middle, middle, low-middle and low Socio-demographic Index (SDI) had decline of age-standardised DALY rate of 4.3%, 5.2%, 16.0%, 21.4% and 11.30% from 1990 to 2019, respectively. The poorest 50% of world citizens bore 59.0% and 66.2% of the burden of blindness and vision loss in 1990 and 2019, respectively. The absolute cross-national inequality (SII) fell from -303.5 (95% CI -370.8 to -236.2) in 1990 to -256.0 (95% CI -288.1 to -223.8) in 2019. The relative inequality (concentration index) for global blindness and vision loss remained essentially constant between 1991 (-0.197, 95% CI -0.234 to -0.160) and 2019 (-0.193, 95% CI -0.216 to -0.169).

CONCLUSION

Though countries with middle and low-middle SDI were the most successful in decreasing burden of blindness and vision loss, a high level of cross-national health inequality persisted over the past three decades. More attention must be paid to the elimination of avoidable blindness and vision loss in low-income and middle-income countries.

Price tag of glaucoma care is minor compared with the total direct and indirect costs of glaucoma: Results from nationwide survey and register data

BACKGROUND

The estimations of the economic burden of glaucoma have focused on comparing different treatment modalities; hence, the total direct and indirect costs of glaucoma at population level are not well known.

OBJECTIVE

To estimate the direct and indirect costs of glaucoma and its treatment in Finland.

METHODS

Economic and glaucoma data were collected from the cross-sectional nationwide Health 2000 health examination survey linked to multiple national registers, which allowed a 13-year follow-up between 1999-2011 among survey participants. Direct costs covered eye- and non-eye-related hospitalizations and outpatient visits, outpatient health care services, and travel costs among participants aged 30 years or older, adjusted for age and sex. Indirect costs covered premature retirement and productivity losses among participants aged 30-64 years. Glaucoma patients (n = 192) were compared with non-glaucomatous population (n = 6,952).

RESULTS

The annual additional total direct costs were EUR 2,660/glaucoma patient, EUR 1,769/glaucoma patient with medication, and EUR 3,979/operated glaucoma patient compared with persons without glaucoma. The respective additional total indirect costs were EUR 4,288, EUR 3,246, and EUR 12,902 per year. In total, the additional annual direct and indirect expenditures associated with glaucoma in Finland were EUR 202 million (0.86% of total expenditures of health care) and EUR 71 million (0.03% of the Finnish gross domestic product) arising mainly from non-eye-related hospitalizations and productivity losses, respectively.

CONCLUSION

Glaucoma is associated with an increased health care consumption mainly due to non-eye-related health care, which can be explained by the vision loss as well as increased number of co-morbidities among glaucoma patients. Therefore, glaucoma constitutes a major economic burden for the health care system and society, highlighting the importance of early glaucoma interventions. The difference in direct and indirect costs between glaucoma treatment groups is explained by the uneven distribution of co-morbidities.

The case for investment in eye health: systematic review and economic modelling analysis

Objective

To assess how the returns on investment from correcting refractive errors and cataracts in low- and middle-income countries compare with the returns from other global development interventions.

Methods

We adopted two complementary approaches to estimate benefit-cost ratios from eye health investment. First, we systematically searched PubMed® and Web of Science™ on 14 August 2023 for studies conducted in low-and-middle-income countries, which have measured welfare impacts associated with correcting refractive errors and cataracts. Using benefit-cost analysis, we compared these impacts to costs. Second, we employed an economic modelling analysis to estimate benefit-cost ratios from eye health investments in India. We compared the returns from eye health to returns in other domains across global health and development.

Findings

We identified 21 studies from 10 countries. Thirteen outcomes highlighted impacts from refractive error correction for school students. From the systematic review, we used 17 out of 33 outcomes for benefit-cost analyses, with the median benefit-cost ratio being 36. The economic modelling approach for India generated benefit-cost ratios ranging from 28 for vision centres to 42 for school eye screening, with an aggregate ratio of 31. Comparing our findings to the typical investment in global development shows that eye health investment returns six times more benefits (median benefit-cost ratio: 36 vs 6).

Conclusion

Eye health investments provide economic benefits with varying degrees based on the intervention type and location. Our findings underline the importance of incorporating eye health initiatives into broader development strategies for substantial societal returns.

Improving visual outcomes in patients with rare paediatric eye diseases

Introduction

Rare paediatric eye diseases (RPEDs) threaten both vision and life. Recently, rare diseases were recognised as a global public health agenda, with children specified as a priority in the World Health Organization's VISION 2020 against avoidable visual loss.

Method

We conducted a review through a query of online databases (PubMed, Embase and Cochrane Library). Articles related to RPEDs were selected based on relevance by 2 authors, with any disagreements adjudicated by the third author.

Results

We synthesise the current state of knowledge regarding RPEDs, barriers to their care, and recommendations for the future. RPEDs often result in significant visual loss, profoundly impacting the way children comprehend and participate in the world. These diseases may also reduce life expectancy and even be life-threatening. Barriers to the care of RPEDs include an unclear definition of "rare diseases", missed or delayed diagnosis, inadequate knowledge and expertise in management, and challenging research environments.

Conclusion

Our findings provide an update on the diagnosis and management of RPEDs, which is of relevance to ophthalmologists, paediatricians, healthcare policymakers and social workers. We propose supportive policies and adequate resource allocation to these diseases, comprehensive and patient-centred care, alongside improved education and training, enhanced research capabilities and continued collaboration across institutions.

Save our Sight (SOS): a collective call-to-action for enhanced retinal care across health systems in high income countries

With a growing aging population, the prevalence of age-related eye disease and associated eye care is expected to increase. The anticipated growth in demand, coupled with recent medical advances that have transformed eye care for people living with retinal diseases, particularly neovascular age-related macular degeneration (nAMD) and diabetic eye disease, has presented an opportunity for health systems to proactively manage the expected burden of these diseases. To do so, we must take collective action to address existing and anticipated capacity limitations by designing and implementing sustainable strategies that enable health systems to provide an optimal standard of care. Sufficient capacity will enable us to streamline and personalize the patient experience, reduce treatment burden, enable more equitable access to care and ensure optimal health outcomes. Through a multi-modal approach that gathered unbiased perspectives from clinical experts and patient advocates from eight high-income countries, substantiated perspectives with evidence from the published literature and validated findings with the broader eye care community, we have exposed capacity challenges that are motivating the community to take action and advocate for change. Herein, we propose a collective call-to-action for the future management of retinal diseases and potential strategies to achieve better health outcomes for individuals at-risk of, or living with, retinal disease.

Identification of biomarkers associated with immune scores in diabetic retinopathy

Background

Diabetic retinopathy (DR) causes irreversible visual impairment in diabetes mellitus (DM) patients. Immunity played a crucial role in DR. Nevertheless, the triggering mechanism of DR was not yet thorough enough. Herein, we aim to identify the immune-associated genes as biomarkers associated with immune scores that can distinguish early DR from DM without DR.

Methods

In this study, total RNA of peripheral blood mononuclear cell (PBMC) samples from 15 non-proliferative DR patients and 15 DM patients without DR were collected and the transcriptome sequencing data were extracted. Firstly, the target genes were obtained by intersecting the differentially expressed genes (DEGs), which were screened by "limma", and the module genes (related to immune scores), which were screened by "WGCNA". In order to screen for the crucial genes, three machine learning algorithms were implemented, and a receiver operating characteristic (ROC) curve was used to obtain the diagnostic genes. Moreover, the gene set enrichment analysis (GSEA) was performed to understand the function of diagnostic genes, and analysis of the proportions of immune cells and their association with diagnostic genes was performed to analyze the pathogenesis of DR. Furthermore, the regulatory network of TF-mRNA-miRNA was built to reveal the possible regulation of diagnostic genes. Finally, the quantitative real-time polymerase chain reaction (qRT-PCR) was performed to verify the mRNA level of diagnostic genes.

Results

A total of three immune-associated diagnostic genes, namely, FAM209B, POM121L1P, and PTGES, were obtained, and their expression was increased in PBMC samples of DR, and qRT-PCR results confirmed these results. Moreover, the functions of these genes were associated with immune response. The expression of POM121L1P and PTGES was significantly negatively associated with naive B cells, and the expression of FAM209B was significantly negatively associated with immature dendritic cells. Moreover, ESR1 could regulate both FAM209B and PTGES.

Conclusion

This study identified three immune-associated diagnostic genes, FAM209B, POM121L1P, and PTGES, as biomarkers associated with immune scores in DR for the first time. This finding might proffer a novel perspective of the triggering mechanism of DR, and help to understand the role of immune-associated genes in the molecular mechanism of DR more deeply.

Nationwide and regional trends in distance and near visual acuities during 2000-2017 in Finland

PURPOSE

To evaluate time trends in distance and near vision at the national and regional levels during 2000-2017 in Finland.

METHODS

We used three cross-sectional, nationwide health examination surveys representing the Finnish adult population aged 30 years or older in 2000, 2011 and 2017. Bilateral, habitual distance and near visual acuity (VA) were measured in all three surveys.

RESULTS

The prevalence of good distance vision (VA ≥ 1.0) increased from 76.7% to 81.3% during 2000-2017 while the prevalence of weak or worse distance vision (VA ≤ 0.5) decreased from 7.6% to 3.7%. The improvements were largest among those aged 85 years and older: the prevalence of distance VA ≤ 0.5 decreased from 71.8% to 28.3%. Near vision showed improvement to a lesser extent in the total population; nevertheless, among those aged 85 years and older the prevalence of weak or worse near vision (VA ≤ 0.5) decreased from 62.3% to 27.1%. A similar positive time trend was observed in all main regions of Finland, and differences between urban and rural regions were small.

CONCLUSION

During the past two decades, the overall vision level has improved among the adult population. This is explained mostly by a positive shift from lower to higher vision levels among older age groups, indicating that people live longer with good or adequate vision. This positive trend showed remarkable similarity throughout different regions in Finland, highlighting the importance of equal and accessible eye care throughout the country.

The burden of vision loss in the Middle East and North Africa region, 1990-2019

BACKGROUND

The loss of vision is a substantial public health concern that has important implications for an individual's quality of life. The primary objective of this research was to document the burden of vision loss in the Middle East and North Africa (MENA) region, spanning the years 1990-2019, by age group, sex, underlying cause and sociodemographic index (SDI).

METHODS

Publicly available data concerning the burden of vision loss were acquired from the Global Burden of Disease study 2019. The data encompassed all 21 countries within the MENA region for the period spanning 1990 to 2019. The estimates were reported as raw counts and age-standardised rates per 100,000, accompanied by their corresponding 95% uncertainty intervals (UIs).

RESULTS

In 2019, MENA had an age-standardised point prevalence of 7040.0 (95% UI: 6195.0, 8002.7) and an YLD rate of 314.5 (222.1, 427.6) per 100,000 for vision loss, which were 11.1% (-12.5, -9.7) and 24.3% (-27.6, -20.8) lower, respectively, than in 1990. In 2019, Afghanistan [469.6 (333.0, 632.8)] had the largest age-standardised YLD rate and Turkey [210.7 (145.3, 290.9)] had the lowest. All countries showed a decrease in the age-standardised point prevalence and YLD rate between 1990 and 2019, except for Oman, Afghanistan, and Yemen. Furthermore, in 2019 the largest number of prevalent cases and YLDs were found in the 65-69 age group. Also in 2019, the age-standardised YLD rates in MENA exceeded the global averages for most age groups, for both males and females. In 2019, refractive disorders were the most common types of vision loss among children, adolescents, and middle-age adults in MENA, while near vision loss and cataracts were the most common among older adults. Finally, the burden of vision loss had a slightly negatively association with SDI over the period 1990-2019.

CONCLUSION

Although the burden of vision loss has decreased over the last three decades, the prevalence remains high. These results underscore the importance of healthcare policymakers taking action to implement preventive measures, especially among the elderly and those living in low socioeconomic countries, to decrease the attributable burden in MENA.

Clinical Research on the Leading Causes of Severe Sight Impairment in the UK General and Working Populations

Purpose

Clinical research brings the potential of improved diagnostics, sight-saving treatments, and more accessible services to those suffering with severe sight impairment (SSI). This report investigates whether registered ophthalmology clinical studies address the leading causes of SSI in the general and working populations of the United Kingdom (UK).

Methods

The latest statistics on the leading causes of SSI in the UK general and working populations were identified by searching PubMed, Cochrane Library, and TRIP databases. Clinical study registries were searched to identify registered clinical studies (on or prior to 1st December 2022) on the leading causes of SSI. The relationship between the number of clinical studies on leading causes of SSI and the percentage of SSI certifications they account for was analyzed.

Results

In the UK general population, the number of registered clinical studies on the leading causes of SSI is statistically significantly correlated (Spearman's rho = 0.86, p < 0.01) with the percentage of SSI certifications they account for. However, there is no correlation between the two in the UK working population (aged 16-64) (Spearman's rho = 0.15, p = 0.70). Eye conditions accounting for the most SSI certifications in individuals of working age have significantly less clinical research activity than those that cause the most SSI certifications in the general population. Out of the leading causes of SSI certifications studied, disorders of the visual cortex and congenital anomalies of the eye have the least clinical research activity.

Conclusion

Clinical research into the leading causes of SSI in the general population is essential. However, it is important to consider eye conditions that cause the most severe visual impairment in individuals of working age due to the significant health and socioeconomic implications of sight loss in this population.

Cost-effectiveness of cytomegalovirus vaccination for females in China: A decision-analytical Markov study

BACKGROUND

The global burden of disease caused by congenital cytomegalovirus (CMV) infection is high. Previous modeling studies have suggested that CMV vaccination may be cost-effective in developed countries. Congenital CMV infection is more likely driven by maternal non-primary infection in China. We aimed to measure the effectiveness and cost-effectiveness of population-level CMV vaccination in Chinese females.

METHODS

A decision tree Markov model was developed to simulate potential CMV vaccination strategies in a multi-cohort setting, with a population size of 1,000,000 each for the infant, adolescent (10-year-old) and young adult (20-year-old) cohorts. The hypothetical vaccines were assumed to have 50% efficacy, 20 years of protection, 70% coverage, at a price of US$120/dose for base-case analysis. Costs and disability-adjusted life years (DALYs) were discounted by 3% per year and the vaccination would be considered cost-effective if an incremental cost-effectiveness ratio (ICER) was lower than 2021 Chinese per capita GDP (US$12,500).

FINDINGS

For the pre-infection (PRI) vaccine efficacy type, the adolescent strategy was the most cost-effective, with an ICER of US$12,213 (12,134 to 12,291) pre DALY averted, compared with the next best strategy (young adult strategy). For pre- and post-infection (P&PI) efficacy type, the young adult strategy was the most cost-effective as it was cost-saving. In one-way analysis varying the PRI vaccine price, the infant strategy, adolescent strategy and the young adult strategy would be a dominant strategy over others if the vaccine cost ≤US$60, US$61-121 and US$122-251 per dose respectively. In contrast, the young adult strategy continued to be the preferred strategy until the P&PI vaccine price exceeded US$226/dose. Our main results were robust under a wide variety of sensitivity analyses and scenario analyses.

INTERPRETATION

CMV vaccination for females would be cost-effective and even cost-saving in China. Our findings had public health implications for control of CMV diseases.

The Patients' Perspective for the Impact of Late Detection of Ocular Diseases on Quality of Life: A Cross-Sectional Study

Background

Late detection of ocular diseases negatively affects patients' quality of life (QoL), encompassing health status, psychological, financial, and social aspects. However, the early detection of eye conditions leads to rapid intervention and avoiding complications, thus preserving the QoL. This study assessed the impact of ocular diseases late detection on patients' QoL at multi-eye clinics based on questionnaire responses.

Methods

We developed an original Arabic-English questionnaire to assess the QoL of patients with ocular diseases referred from primary and secondary healthcare centers to tertiary hospitals. It covered preliminary data, patient perspectives on having lately detected ocular disease and treatment costs, and the impact of late detection on finances, social life, psychology, health status, and awareness of current initiatives. Logistic regression analysis was used to explore the associations between patient perspectives on having ocular diseases detected at a late stage and its impact on different domains. Multivariate logistic regression was applied with impact types of health status, psychological, financial, and social (dependent variables) and age, income levels, and hospital type (independent variables).

Results

Three hundred and eighty-eight responded, with 50% experiencing psychological effects, 27% health issues, 23% social impacts, and 23% financial burdens. Two hundred seventeen patients (56%) reported having ocular condition detected in late stage. Logistic regression analysis showed positive association with health status, social well-being, and financial effects (p < 0.05). Multivariate analysis revealed pronounced effects in patients ≤ 50 years, with income \< 5000 SAR, and those visiting private clinics (p < 0.05). The social impact was greater in patients visiting private hospitals. Ninety percent of all patients emphasized the importance of increasing awareness for better QoL.

Conclusion

Significant associations were found between the late detection of eye diseases and their impact on QoL. Therefore, early detection and increasing patients' awareness of ocular diseases and treatment are essential.

Metabolic syndrome as an independent risk factor for glaucoma: a nationally representative study

BACKGROUND

Central insulin resistance contributes to glaucoma development. Given the close association between metabolic syndrome MetS and insulin resistance, this study aimed to determine whether MetS is associated with glaucoma risk.

METHODS

We analyzed data from 11,499 adults aged ≥ 19 years in the 2019-2021 Korean National Health and Nutrition Examination Survey and applied sampling weights to represent the general Korean population. Participants were classified into groups with or without MetS. Ocular hypertension (HTN) was defined as intraocular pressure > 21 mmHg. Primary open-angle glaucoma (POAG) was diagnosed based on the results of a visual field test and optical coherence tomography using the criteria published by the International Society for Geographic and Epidemiological Ophthalmology. We further divided POAG into normal tension (NTG) and POAG with ocular HTN. A spline curve was drawn to determine the dose-response relationship between the number of MetS components and risk of POAG. Odds ratios (ORs) with 95% confidence interval (CI) for POAG according to MetS status were estimated using weighted logistic regression analyses.

RESULTS

The prevalence of POAG was 5.7% and 3.5%, respectively, in groups with and without MetS. We identified a dose-response relationship between the number of MetS components and risk of POAG. Unadjusted ORs (95% CI) for POAG in the group with MetS was 1.85 (1.52-2.25), compared with those without MetS. The trends persisted in adjusted models. The fully-adjusted OR (95% CI) for POAG was 1.47 (1.04-2.09) in the group with MetS. Subgroup analysis revealed that a significant relationship remained only in the NTG group (fully adjusted OR, 1.50; 95% CI 1.05-2.15).

CONCLUSIONS

A comprehensive ophthalmological assessment should be considered for persons with MetS who are at increased risk of POAG, particularly NTG.

The Host-Pathogen Interplay: A Tale of Two Stories within the Cornea and Posterior Segment

Ocular infectious diseases are an important cause of potentially preventable vision loss and blindness. In the following manuscript, we will review ocular immunology and the pathogenesis of herpesviruses and Pseudomonas aeruginosa infections of the cornea and posterior segment. We will highlight areas of future research and what is currently known to promote bench-to-bedside discoveries to improve clinical outcomes of these debilitating ocular diseases.

The health care and societal costs of inherited retinal diseases in Australia: a microsimulation modelling study

OBJECTIVES

To estimate the health care and societal costs of inherited retinal diseases (IRDs) in Australia.

DESIGN, SETTING, PARTICIPANTS

Microsimulation modelling study based on primary data - collected in interviews of people with IRDs who had ophthalmic or genetic consultations at the Children's Hospital at Westmead or the Save Sight Institute (both Sydney) during 1 January 2019 - 31 December 2020, and of their carers and spouses - and linked Medicare Benefits Schedule (MBS) and Pharmaceutical Benefits Schedule (PBS) data.

MAIN OUTCOME MEASURES

Annual and lifetime costs for people with IRDs and for their carers and spouses, grouped by payer (Australian government, state governments, individuals, private health insurance) and type (health care costs; societal costs: social support, National Disability Insurance Scheme (NDIS), income and taxation, costs associated with caring for family members with IRDs); estimated annual national cost of IRDs.

RESULTS

Ninety-four people (74 adults, 20 people under 18 years; 55 girls and women [59%]) and 30 carers completed study surveys (participation rate: adults, 66%; children, 66%; carers, 63%). Total estimated lifetime cost was $5.2 million per person with an IRD, of which 87% were societal and 13% health care costs. The three highest cost items were lost income for people with IRDs ($1.4 million), lost income for their carers and spouses ($1.1 million), and social spending by the Australian government (excluding NDIS expenses: $1.0 million). Annual costs were twice as high for people who were legally blind as for those with less impaired vision ($83 910 v $41 357 per person). The estimated total annual cost of IRDs in Australia was $781 million to $1.56 billion.

CONCLUSION

As the societal costs associated with IRDs are much larger than the health care costs, both contributors should be considered when assessing the cost-effectiveness of interventions for people with IRDs. The increasing loss of income across life reflects the impact of IRDs on employment and career opportunities.

Evaluation of the better operative outcome software tool to predict cataract surgical outcome in the early postoperative follow-up

BACKGROUND

Cataracts are the world's leading cause of avoidable blindness. In low-income countries, there are high rates of poor follow-up, which makes it very difficult to monitor surgical outcomes. To address this issue, the Better Operative Outcome Software Tool (BOOST Cataract app) predicts outcome on the first postoperative day and provides specific advice to improve outcomes. The aim of the study is to evaluate the ability of the BOOST Cataract app to categorise surgical outcomes and to analyse the possible factors that contribute to its performance. This was a prospective observational study performed at the General Hospital of Hospitalet of Llobregat.

RESULTS

A total of 126 cataracts were included. Patients had a mean [SD] age of 75.8 [12.19] years, and 52% were females. Manual small-incision cataract surgery was involved in 57% and phacoemulsification in 43%. Thirty-eight percent of eyes presented significant corneal oedema on day 1. The BOOST Cataract app succeeded in categorising the final outcome in 65.6% of the eyes and in 93,4% of the eyes with good outcome.The agreement between the BOOST and UDVA outcomes was 0.353 (p< .000). The level of agreement improved to 0.619 (p< .000) in eyes with clear corneas. Success obtained by BOOST for both types of surgery was not statistically different. Eyes that obtained a good outcome on day one after surgery and eyes with clear cornea had 37 times higher odds (95% CI 6.66, 212.83) and 12 times higher odds (95% CI 3.13, 47.66) of being correctly categorised by the BOOST Cataract app than eyes that obtained a suboptimal (moderate and poor) outcome and eyes with corneal oedema on day 1.

CONCLUSIONS

The BOOST Cataract app is an e-Health tool designed to address issues of measuring quality in low- and middle-income settings. Although its reliability is limited to eyes that obtain a good outcome and with clear corneas on day 1, the use of the tool on a regular basis facilitates monitoring and reporting outcomes when clinical data collection is challenging due to low postoperative follow-up rates.

Timing is Everything: Stochastic Optogenetic Stimulation Reduces Adaptation in Retinal Ganglion Cells

Optogenetics gives us unprecedented power to investigate brain connectivity. The ability to activate neural circuits with single cell resolution and its ease of application has provided a wealth of knowledge in brain function. More recently, optogenetics has shown tremendous utility in prosthetics applications, including vision restoration for patients with retinitis pigmentosa. One of the disadvantages of optogenetics, however, is its poor temporal bandwidth, i.e. the cell's inability to fire at a rate that matches the optical stimulation rate at high frequencies (>30 Hz). This research proposes a new strategy to overcome the temporal limits of optogenetic stimulation. Using whole-cell current clamp recordings in mouse retinal ganglion cells expressing channelrhodopsin-2 (H134R variant), we observed that randomizing inter-pulse intervals can significantly increase a retinal ganglion cell's temporal response to high frequency stimulation.Clinical Relevance- A significant disadvantage of optogenetic stimulation is its poor temporal dynamics which prohibit its widespread use in retinal prosthetics. We have shown that randomizing the interval between stimulation pulses reduces adaptation in retinal ganglion cells. This stimulation strategy may contribute to new levels of functional restoration in therapeutics which incorporate optogenetics.

The effect of social determinants of health on severity of microbial keratitis presentation at a tertiary eye care hospital in Southern India

Purpose

Understanding the association between social determinants of health (SDoHs) and microbial keratitis (MK) can inform underlying risk for patients and identify risk factors associated with worse disease, such as presenting visual acuity (VA) and time to initial presentation.

Methods

This was a cross-sectional study was conducted with patients presenting with MK to the cornea clinic at a tertiary care hospital in Madurai, India. Patient demographics, SDoH survey responses, geographic pollution, and clinical features at presentation were collected. Descriptive statistics, univariate analysis, multi-variable linear regression models, and Poisson regression models were utilized.

Results

There were 51 patients evaluated. The mean age was 51.2 years (SD = 13.3); 33.3% were female and 55% did not visit a vision center (VC) prior to presenting to the clinic. The median presenting logarithm of the minimum angle of resolution (logMAR) VA was 1.1 [Snellen 20/240, inter-quartile range (IQR) = 20/80 to 20/4000]. The median time to presentation was 7 days (IQR = 4.5 to 10). The average particulate matter 2.5 (PM2.5) concentration, a measure of air pollution, for the districts from which the patients traveled was 24.3 μg/m3 (SD = 1.6). Age- and sex-adjusted linear regression and Poisson regression results showed that higher levels of PM2.5 were associated with 0.28 worse presenting logMAR VA (Snellen 2.8 lines, P = 0.002). Patients who did not visit a VC had a 100% longer time to presentation compared to those who did (incidence rate ratio = 2.0, 95% confidence interval = 1.3-3.0, P = 0.001).

Conclusion

Patient SDoH and environmental exposures can impact MK presentation. Understanding SDoH is important for public health and policy implications to mitigate eye health disparities in India.

Economic Evaluation of Cataract: A Systematic Mapping Review

INTRODUCTION

The purpose of this article was to ascertain the existing literature and find the gaps in economic evaluations of cataracts.

METHODS

Systematic methods were used to search and collect the published literature on economic evaluations of cataracts. A mapping review of studies published in the following bibliographical databases was performed: the National Library of Medicine (PubMed), EMBASE, Web of Science (WOS), and the Central of Reviews and Dissemination (CRD) database. A descriptive analysis was conducted and relevant studies were classified into different groups.

RESULTS

Among 984 studies screened, 56 studies were included in the mapping review. Four research questions were answered. There has been a progressive increase of publications during the last decade. The majority of the included studies were published by authors from institutions in the USA and UK. The most commonly investigated area was cataract surgery followed by intraocular lenses (IOLs). The studies were classified into different categories according to the main outcome evaluated, such as comparisons between different surgical techniques, costs of the cataract surgery, second eye cataract surgery costs, quality of life gain after cataract surgery, waiting time of cataract surgery and costs, and cataract evaluation, follow-up, and costs. In the IOL classification, the most frequently studied area was the comparison between monofocal and multifocal IOLs, followed by the comparison between toric and monofocal IOLs.

CONCLUSIONS

Cataract surgery is a cost-effective procedure compared with other non-ophthalmic and ophthalmic interventions and surgery waiting time is an important factor to consider because vision loss has a huge and broad-ranging impact on society. Numerous gaps and inconsistencies are found among the studies included. For this reason, there is a need for further studies according to the classification described in the mapping review.

Adherence to referrals from preschool vision screening and identification of barriers for non-adherence in Israel

CLINICAL RELEVANCE

Preschool vision screening is essential for the early detection and treatment of eye and vision problems.

BACKGROUND

The rate of parental adherence to referrals for comprehensive examination was assessed and factors and potential barriers associated with adherence were identified.

METHODS

In a prospective cohort study design, parents were offered to bring their 3-6 year old aged children to free-of-charge vision screening tests at community-based Mother Child Health Centers. Children with abnormal findings were referred to an ophthalmologist examination. Parents were interviewed three to six months after the referral to evaluate adherence and barriers. Barriers were organised into a conceptual framework of parental predisposing and health system factors. Adherence and barriers were assessed by sex, age, ethnic group and socio-economic-status.

RESULTS

Altogether 1283 children (mean age 4.5 ± 0.6 years, 47.8% girls) were screened in the Jerusalem district, Israel. The ethnic groups, Jewish (ultra-Orthodox 51.4%, secular/religious 33.2%) and Arab (15.4%), were similar by age and sex, but not by socio-economic status. The overall referral rate was 23.0% (N = 295). Referral rate was not associated with demographic factors. Overall, 54.3% (N = 160) of parents adhered to the referral to bring the child for a full eye examination. Adherence did not differ with sex, ethnicity or socio-economic-status. Parents of 5-6-year-old children were significantly more likely to adhere than parents of younger children. Of parents who did not adhere, 79.3% were attributed to predisposing factors, 16.3% to system factors and 4.4% to other reasons.

CONCLUSIONS

Only half the parents proceeded with the recommended full eye examination. Parents of older children were more likely to adhere to referral. In contrast with vaccinations provided by Mother Child Health Centers, adherence to vision screening did not vary based on ethnicity or socio-economic factors. Since most barriers were associated with predisposing factors of parents, interventions to improve adherence should include parental education.

Prevalence of refractive errors in Nepalese children and adults: a systematic review with meta-analysis

CLINICAL RELEVANCE

Country-specific estimates of the prevalence of refractive errors are important to formulate national eye health policies for refractive care services.

BACKGROUND

The purpose of this study was to systematically synthesise available literature and estimate the prevalence of refractive errors in the Nepalese population.

METHODS

PubMed, Scopus, and Web of Science databases were systematically searched for articles on refractive errors and presbyopia published in English language until 27 September 2022. Population and school-based quantitative, cross-sectional prevalence studies and Rapid Assessment of Avoidable Blindness survey repository data were included. The quality of the included studies was assessed using the Newcastle Ottawa scale adapted for cross-sectional studies. Data extraction was performed with consensus among the reviewers. Meta-analysis of the prevalence was performed using the Random effects model to estimate the pooled proportions.

RESULTS

A total of 38 studies with 101 701 participants were included: 18 studies in children (n = 31 596) and 20 in adults (n = 70 105). In children, the estimated pooled prevalence of overall refractive errors was 8.4% (95% CI: 4.8 to 12.9) with myopia, hypermetropia and astigmatism prevalent in 7.1% (95% CI: 3.7 to 11.4), 1.0% (95% CI: 0.7 to 1.3) and 2.2% (95% CI: 0.9 to 3.9), respectively. In adults, the prevalence of refractive errors, uncorrected refractive errors, and uncorrected presbyopia were 11.2% (95% CI: 8.0 to 14.9), 7.3% (95% CI: 5.4 to 9.5) and 78.9% (95% CI: 69.1 to 87.3), respectively.

CONCLUSIONS

The pooled prevalence of refractive errors is relatively low while uncorrected refractive errors and presbyopia are high in Nepalese population suggesting a need for better access to refractive care services in the country. The paucity of quality evidence on prevalence of refractive errors, particularly in children, indicates a need for a well-designed population-based study to accurately estimate the current prevalence of refractive errors.

A National Registry-Based Epidemiological Study to Evaluate 395 646 Patients Hospitalized Due to Eye Diseases in Poland in 2019

BACKGROUND The Nationwide General Hospital Morbidity Study Registry collects demographic, health, and medical data on patients hospitalized throughout Poland, and acts as a registry for epidemiological, public health, and hospital administrative studies. This epidemiological national registry-based study aimed to evaluate the characteristics of 395 646 patients hospitalized due to eye diseases in Poland in 2019. MATERIAL AND METHODS This study is a retrospective nationwide registry-based analysis. Data on all patients hospitalized due to eye diseases in 2019 were obtained from the Nationwide General Hospital Morbidity Study Registry. Demographic characteristics of patients hospitalized due to eye diseases as well as the hospitalization course were analyzed using descriptive epidemiology tools. RESULTS Disorders of the lens accounted for 68.6% of all hospital admissions, and disorders of the choroid and retina were the second most common (13.9%) cause of hospital admission due to eye diseases in 2019. Over three-quarters of hospital admissions (77.4%) lasted less than 24 h, and 86.8% were scheduled admissions. Most of the patients hospitalized due to eye diseases were females (59.9%) and over 70% lived in urban areas. There were regional differences in the hospital admissions rate per 100 000 inhabitants. According to the data presented in the registry, less than one-third of patients had comorbidities. CONCLUSIONS Hospital ophthalmological care in Poland is based mainly on planned hospitalizations lasting less than 24 h and related to ophthalmological surgery. Data on the comorbidity of ophthalmologic patients suggest that ophthalmologists do not pay enough attention to identifying and recording the patient's health status.

Associations of exposure to multiple metals with the risk of age-related cataract in Anhui, China: a case-control study

It's well-known that multiple metal elements can lead to the change of oxidative stress response levels in vivo. However, their relationship with age-related cataract (ARC) had not been well studied. We designed a case-control study including 210 individuals with ARC and 210 matched control group. The metal levels in their urine specimens were measured using graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma optical emission spectrometry (ICP-OES). Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to select representative metals into the multi-element model and reduce dimension. Multivariate logic analysis and Bayesian kernel machine regression (BKMR) were subsequently used to explore the association of ARC risk with multiple metal elements. We found that magnesium (Mg), chromium (Cr), arsenic (As), manganese (Mn), and selenium (Se) were positively associated with ARC in the single-element model. The multiple exposure model indicated a positive association between Mg and As, in which the OR in their highest quartile were 3.32 (95% CI: 1.24-8.89) and 7.09 (95% CI: 2.56-19.63). The BKMR model also showed the effect of As increased monotonically with its increasing concentration, and high levels of Mg and As had a significant positive effect on ARC risk. In conclusion, we found that exposure to multiple metals was associated with increased ARC risk. Further research is needed to verify these findings in the future.

Cataract Surgery in Low-Income Countries: A Good Deal!

Cataract is a major cause of blindness worldwide. In particular, in low-income countries, the burden of disease as well as its direct and indirect economic cost are a major challenge for the population and economy. In many cases, it would be possible to prevent or cure blindness with a comparably simple cataract surgery, but many countries lack the resources to strengthen healthcare systems and implement broad cataract surgery programs reaching, in particular, the rural poor. In this paper, we analyse whether such an intervention could be cost-effective or even cost-saving for the respective health systems. We calculate the net value of the lifelong costs of cataract with and without surgery. This calculation includes direct costs (e.g., treatment, glasses, surgery) as well as indirect cost of the caregiver and the patient. We total all costs from the year of onset of cataract until death and discount the respective values to the year of onset. We define the surgery as cost-saving if the net-value of costs with surgery is lower than without surgery. If the cost per quality adjusted life year is lower than one gross national product per capita, we define the intervention as highly cost-effective. We find that the cost-effectiveness of cataract surgery depends on the age of onset of the disease and the age of surgery. If the surgery is performed with the beginning of severe impairment, even surgery of a 78-year-old patient is still cost-saving. Almost all possible constellations are highly cost-effective, only for the very old it is questionable whether the surgery should be performed. The simulations show that cataract surgery is one of the most cost-effective interventions. However, millions of people in low-income countries still have no chance to prevent or cure blindness due to limited resources. The findings of this paper clearly call for a stronger effort to reach poor and rural populations with this cost-effective service.

The Basic VRS-Effect Study: Clinical Trial Outcomes and Cost-Effectiveness of Low Vision Rehabilitation in Portugal

INTRODUCTION

The aim of this study was twofold: (1) to investigate the clinical impact of vision rehabilitation in patients with vision impairment and (2) to investigate the cost-effectiveness of a basic vision rehabilitation service in Portugal.

METHODS

The trial recruited patients diagnosed with age-related macular degeneration or diabetic retinopathy (DR) and visual acuity in the range 0.4-1.0logMAR in the better-seeing eye. Participants were randomised to one of the study arms consisting of immediate intervention and delayed intervention. The intervention included: new refractive correction, optical reading aids, in-office training and advice about modifications at home. Visual ability, health-related quality of life and costs were measured. Economic analysis was performed to evaluate whether the intervention was cost-effective. The trial compared the outcomes 12 weeks after the start in both arms.

RESULTS

Of the 46 participants, 34 (74%) were diagnosed with DR, 25 (54%) were female, and mean age was 70.08 years (SD = 8.74). In the immediate intervention arm visual ability increased a mean of 0.523 logits (SE = 0.11) (p < 0.001). Changes in the delayed intervention arm were not statistically significant (p = 0.95). Acuity in the better-seeing eye, near acuity and critical print size also improved during the study. The mean cost of the intervention was €118.79 (SD = 24.37). The incremental cost-effectiveness ratio using the EQ-5D-5L was 30,421€/QALY and 1186€/QALY when using near acuity.

CONCLUSION

The current study gives evidence of positive clinical impact of a basic vision rehabilitation intervention and shows that a basic vision rehabilitation service is cost-effective. These findings are important to clinical and rehabilitation practices and for planning vision rehabilitation services.

TRIAL REGISTRATION

Retrospectively registered, 21/01/2019. ISRCTN10894889, https://www.isrctn.com/ISRCTN10894889.

Analysis of Drug Clinical Trials for Eye Diseases in China

Purpose: We systematically retrospected and analyzed the general characteristics of ophthalmic drug clinical trials (CTs) registered in China from January 2014 to December 2021. Methods: Data were retrieved from the Drug Trial Registration and Information Publication Platform and then standardized and statistically classified using bibliometric analysis. Results: We identified 201 drug CTs for eye diseases, including 24 international multicenter trials. The number of drug CTs for eye diseases has considerably increased since 2017 in parallel with new policies to encourage innovation in drugs and medical devices in China. The drug types consist of biologicals (48.26%), chemicals (45.77%), and traditional Chinese medicine/natural medicines (5.97%). The main indications were age-related macular degeneration (AMD; n = 47, 23.38%), macular edema (n = 32, 15.92%), and diabetic retinopathy (n = 19, 9.45%). The trials included those in phase I (n = 67, 33.33%), phase II (n = 33, 16.42%), and phase III (n = 72, 35.82%). The phase I trials comprised 24 innovative drug treatments for AMD and 6 novel drug treatments for neuromyelitis optica spectrum disorders, with 39 biologicals and 27 chemicals. The trials mostly followed a randomized (84.08%) or masked (67.16%) design, with 90.37% of the latter being double-masked trials. Conclusion: Research and development of ophthalmic drugs have substantially increased in recent years and are influenced by regulatory policies. Among these drugs, biologicals for AMD are the most prevalent, followed by biologicals for macular edema. Randomized double-masked research designs are often used and represent high-quality evidence.

Potential productivity loss from uncorrected and under-corrected presbyopia in low- and middle-income countries: A life table modeling study

Objective

To estimate the burden of potential productivity losses due to uncorrected and under-corrected presbyopia in LMICs among the working-age population in both the cross-sectional and longitudinal manner.

Methods

We extracted data for the prevalence of presbyopia from the Global Burden of Diseases (GBD), Injuries, and Risk Factors Study 2019. Data for the gross domestic product (GDP) per capita were extracted from the World Bank database and Central Intelligence Agency's World Factbook. We introduced life table models to construct age cohorts (in 5-year age groups) of the working-age population (aged from 40 to 64 years old) in LMICs, with simulated follow-up until 65 years old in people with and without uncorrected presbyopia. The differences in productivity-adjusted life years (PALYs) lived and productivity between these two cohorts were calculated. The potential productivity loss was estimated based on GDP per capita. The WHO standard 3% annual discount rate was applied to all years of life and PALYs lived.

Results

In 2019, there were 238.40 million (95% confidence interval [CI]: 150.92-346.78 million) uncorrected and under-corrected presbyopia cases in LMICs, resulting in 54.13 billion (current US dollars) (95% confidence interval [CI]: 34.34-79.02 billion) potential productivity losses. With simulated follow-up until retirement, those with uncorrected and under-corrected presbyopia were predicted to experience an additional loss of 155 million PALYs (an average loss of 0.7 PALYs per case), which was equivalent to a total loss of US$ 315 billion (an average loss of US$ 1453.72 per person).

Conclusions

Our findings highlight the considerable productivity losses due to uncorrected and under-corrected presbyopia in LMICs, especially in a longitudinal manner. There is a great need for the development of enabling eye care policies and programs to create access to eye care services, and more healthcare investment in the correction of presbyopia in the working-age population in LMICs. This study could provide evidences for some potential health-related strategies for socio-economic development.

In Situ-Forming Collagen-Hyaluronate Semi-Interpenetrating Network Hydrogel Enhances Corneal Defect Repair

Purpose

Millions worldwide suffer vision impairment or blindness from corneal injury, and there remains an urgent need for a more effective and accessible way to treat corneal defects. We have designed and characterized an in situ-forming semi-interpenetrating polymer network (SIPN) hydrogel using biomaterials widely used in ophthalmology and medicine.

Methods

The SIPN was formed by cross-linking collagen type I with bifunctional polyethylene glycol using N-hydroxysuccinimide ester chemistry in the presence of linear hyaluronic acid (HA). Gelation time and the mechanical, optical, swelling, and degradation properties of the SIPN were assessed. Cytocompatibility with human corneal epithelial cells and corneal stromal stem cells (CSSCs) was determined in vitro, as was the spatial distribution of encapsulated CSSCs within the SIPN. In vivo wound healing was evaluated by multimodal imaging in an anterior lamellar keratectomy injury model in rabbits, followed by immunohistochemical analysis of treated and untreated tissues.

Results

The collagen-hyaluronate SIPN formed in situ without an external energy source and demonstrated mechanical and optical properties similar to the cornea. It was biocompatible with human corneal cells, enhancing CSSC viability when compared with collagen gel controls and preventing encapsulated CSSC sedimentation. In vivo application of the SIPN significantly reduced stromal defect size compared with controls after 7 days and promoted multilayered epithelial regeneration.

Conclusions

This in situ-forming SIPN hydrogel may be a promising alternative to keratoplasty and represents a step toward expanding treatment options for patients suffering from corneal injury.

Translational Relevance

We detail the synthesis and initial characterization of an SIPN hydrogel as a potential alternative to lamellar keratoplasty and a tunable platform for further development in corneal tissue engineering and therapeutic cell delivery.

LNP-mediated delivery of CRISPR RNP for wide-spread in vivo genome editing in mouse cornea

CRISPR/Cas9-based genome-editing therapies are poised to change the clinical outcome for many diseases with validated therapeutic targets awaiting an appropriate delivery system. Recent advances in lipid nanoparticle (LNP) technology make them an attractive platform for the delivery of various forms of CRISPR/Cas9, including the efficient and transient Cas9/gRNA ribonucleoprotein (RNP) complexes. In this study, we initially tested our novel LNP platform by delivering pre-complexed RNPs and template DNA to cultured mouse cortical neurons, and obtained successful ex vivo genome editing. We then directly injected LNP-packaged RNPs and DNA template into the mouse cornea to evaluate in vivo delivery. For the first time, we demonstrated wide-spread genome editing in the cornea using our LNP-RNPs. The ability of our LNPs to transfect the cornea highlights the potential of our novel delivery platform to be used in CRISPR/Cas9-based genome editing therapies of corneal diseases.

The economic and social costs of visual impairment and blindness in India

Purpose

To provide a current estimate of the economic and social costs (or welfare costs) of visual impairment and blindness in India.

Methods

Using evidence from the recently conducted Blindness and Visual Impairment Survey across India, the Lancet Global Health Commission on Global Eye Health and other sources, we developed an economic model that estimates the costs of reduced employment, elevated mortality risk, education loss for children, productivity loss in employment, welfare loss for the unemployed, and caregiver costs associated with moderate and severe visual impairment (MSVI) and blindness. Probabilistic sensitivity analyses were also conducted by varying key parameters simultaneously.

Results

The costs of MSVI and blindness in India in 2019 are estimated at INR 1,158 billion (range: INR 947-1,427 billion) or $54.4 billion at purchasing power parity exchange rates (range: $44.5-67.0 billion), accounting for all six cost streams. The largest cost was for the loss of employment, whereas the the second largest cost was for caregiver time. A more conservative estimate focusing only on employment loss and elevated mortality risk yielded a cost of INR 504 billion (range: INR 348-621 billion) or $23.7 billion (range: $16.3-29.2 billion).

Conclusion

Poor eye health imposes a non-trivial recurring cost to the Indian economy equivalent to 0.47% to 0.70% of GDP in the primary scenario, a substantial constraint on the country's growth aspirations. Furthermore, the absolute costs of poor eye health will increase over time as India ages and becomes wealthier unless further progress is made in reducing the prevalence of MSVI and blindness.

The effect of poor vision on economic farm performance: Evidence from rural Cambodia

Roughly one-fifth of the global population is affected by poor visual acuity. Despite the fact that inhabitants of rural areas in low-income countries are most distressed by this, no prior research has studied the impact of poor visual acuity on the economic performance of farms. We conduct a standardized eye test with 288 farm managers in rural Cambodia and find that around 30 percent of our sample suffers from poor visual acuity in terms of nearsightedness (myopia). Our analyses indicate a statistically significant and economically meaningful association of poor visual acuity with economic farm performance. Our results show that gross margins for cropping activities per year could be, on average, around 630 USD higher if farm managers were able to correct for poor vision. Our results suggest that poor visual acuity impairs farm managers from tapping the full potential of their business, which in turn decreases their chance to break the vicious cycle of poverty.

Reinforcement learning in ophthalmology: potential applications and challenges to implementation

Reinforcement learning is a subtype of machine learning in which a virtual agent, functioning within a set of predefined rules, aims to maximise a specified outcome or reward. This agent can consider multiple variables and many parallel actions at once to optimise its reward, thereby solving complex, sequential problems. Clinical decision making requires physicians to optimise patient outcomes within a set practice framework and, thus, presents considerable opportunity for the implementation of reinforcement learning-driven solutions. We provide an overview of reinforcement learning, and focus on potential applications within ophthalmology. We also explore the challenges associated with development and implementation of reinforcement learning solutions and discuss possible approaches to address them.

Prevalence of visual impairment due to refractive error among children and adolescents in Ethiopia: A systematic review and meta-analysis

Introduction

Globally, the prevalence of refractive error was 12%, and visual impairment due to refractive error was 2.1%. In sub-Saharan Africa, the prevalence of refractive error and visual impairment due to refractive error was 12.6% and 3.4%, respectively. In Ethiopia, the prevalence of visual impairment due to refractive error varies from 2.5% in the Gurage zone to 12.3% in Hawassa city. Hence, this Meta-analysis aimed to summarize the pooled prevalence of visual impairment due to refractive error in Ethiopia.

Methods

A systematic search of the literature was conducted by the authors to identify all relevant primary studies. All articles on the prevalence of visual impairment due to refractive error in Ethiopia were identified through a literature search. The databases used to search for studies were PubMed, Science Direct, POPLINE, HENARI, Google Scholar, and grey literature was searched on Google until December 15, 2021. In this meta-analysis, the presence of publication bias was evaluated using funnel plots and Begg’s tests at a significance level of less than 0.05. The sensitivity analysis was conducted to check for a single study’s effect on the overall prevalence of refractive error.

Result

About 1664 studies were retrieved from initial electronic searches using international databases and google searches. A total number of 20,088 children and adolescents were included in this meta-analysis. The pooled prevalence of visual impairment due to refractive error in Ethiopia using the random effects model was estimated to be 6% (95% CI, 5–7) with a significant level of heterogeneity (I² = 94.4%; p < 0.001). The pooled prevalence of visual impairment due to refractive was analyzed by subtypes, and pooled prevalence was estimated to be 4%, 5.2%, and 1% for myopia, hyperopia, and astigmatism, respectively.

Conclusion

The pooled prevalence of visual impairment due to refractive error was high in Ethiopia. About one in twenty-five Ethiopian children and adolescents are affected by visual impairment due to myopia.

Current estimates of the economic burden of blindness and visual impairment in India: A cost of illness study

Purpose:

Currently, there are an estimated 4.95 million blind persons and 70 million vision impaired persons in India, out of which 0.24 million are blind children. Early detection and treatment of the leading causes of blindness such as cataract are important in reducing the prevalence of blindness and vision impairment. There are significant developments in the field of blindness prevention, management, and control since the “Vision 2020: The right to sight” initiative. Very few studies have analyzed the cost of blindness at the population level. This study was undertaken to update the information on the economic burden of blindness and visual impairment in India based on the prevalence of blindness in India. We used secondary and publicly available data and a few assumptions for our estimations.

Methods:

We used gross national income (GNI), disability weights, and loss of productivity metrics to calculate the economic burden of blindness and vision impairment based on the “cost of illness” methodology.

Results:

The estimated net loss of GNI due to blindness in India is INR 845 billion (Int$ 38.4 billion), with a per capita loss of GNI per blind person of INR 170,624 (Int$ 7,756). The cumulative loss of GNI due to avoidable blindness in India is INR 11,778.6 billion (Int$ 535 billion). The cumulative loss of GNI due to blindness increased almost three times in the past two decades. The potential loss of productivity due to vision impairment is INR 646 billion (Int$ 29.4 billion).

Conclusion:

These estimates provide adequate information for budgetary allocation and will help advocate the need for accelerated adoption of all four strategies of integrated people-centered eye care (IPCEC). Early detection and treatment of blindness, especially among children, is very important in reducing the economic burden; thus, there is a need for integrating primary eye care horizontally with all levels of primary healthcare.

Update of a Simple Model to Calculate the Annual Global Productivity Loss Due to Blindness and Moderate and Severe Vision Impairment

PURPOSE

To develop a simple but more precise model to calculate potential annual productivity losses due to blindness and moderate and severe vision impairment (MSVI) at the national, regional, and global level.

METHODS

Productivity loss was defined as the loss of minimum wage/Gross National Income per capita (GNI) incurred by people aged 50-64 years with blindness or MSVI, who were not able to work or worked with reduced earnings in 2020. We developed a global list of minimum wage data from on-line sources. All other model data were sourced from international, standardised, and open-access databases. For blindness, the total productivity loss (not working) incurred by 64%-90% of the affected population was summed up with partial productivity loss, defined as 10%-36% of the affected population earning one-third of that of the sighted population. For MSVI, the total productivity loss for 30%-55% of the affected population was summed with the partial productivity loss, defined as 45%-70% of the affected population having 35% reduced earnings. The costs of blindness and MSVI were summed to obtain the cost of combined vision loss.

RESULTS

The global cost of vision loss based on minimum wage was US$160-US$216.32 billion for 2020. The global cost of vision loss using GNI was US$449.36-US$584.66 billion.

CONCLUSIONS

A parsimonious model that considers minimum wage and GNI potentially lost due to blindness and MSVI can be used for eye care programming planning and advocacy at the national, regional, and global level.

Fluorescent Nanosystems for Drug Tracking and Theranostics: Recent Applications in the Ocular Field

The greatest challenge associated with topical drug delivery for the treatment of diseases affecting the posterior segment of the eye is to overcome the poor bioavailability of the carried molecules. Nanomedicine offers the possibility to overcome obstacles related to physiological mechanisms and ocular barriers by exploiting different ocular routes. Functionalization of nanosystems by fluorescent probes could be a useful strategy to understand the pathway taken by nanocarriers into the ocular globe and to improve the desired targeting accuracy. The application of fluorescence to decorate nanocarrier surfaces or the encapsulation of fluorophore molecules makes the nanosystems a light probe useful in the landscape of diagnostics and theranostics. In this review, a state of the art on ocular routes of administration is reported, with a focus on pathways undertaken after topical application. Numerous studies are reported in the first section, confirming that the use of fluorescent within nanoparticles is already spread for tracking and biodistribution studies. The first section presents fluorescent molecules used for tracking nanosystems’ cellular internalization and permeation of ocular tissues; discussions on the classification of nanosystems according to their nature (lipid-based, polymer-based, metallic-based and protein-based) follows. The following sections are dedicated to diagnostic and theranostic uses, respectively, which represent an innovation in the ocular field obtained by combining dual goals in a single administration system. For its great potential, this application of fluorescent nanoparticles would experience a great development in the near future. Finally, a brief overview is dedicated to the use of fluorescent markers in clinical trials and the market in the ocular field.