Social economic development in the prevention of global blindness

A longitudinal study of the association between visual impairment and income change using a national health screening cohort

We evaluated the influence of visual impairment (VI) on income change using the longitudinal database of a Korean National Health Insurance Service cohort. A total of 5292 participants ≥ 40 years old and registered as visually impaired persons were selected at a 1:4 ratio with 45,081 non-VI participants matched for age, sex, and income level. The income level of both the VI and non-VI groups increased over time. In the VI group, the income levels 3, 4 and 5 years were higher than the initial value, while the income levels from 1 through 5 years were increased each year in the non-VI group. The rate of change in income between time and VI were significant. In the subgroup analysis considering age, sex, and severity of VI, the rate of change in income were significant in < 65 years old subgroups. Regarding the severity of VI, a significant interaction was found for the mild-to-moderate VI subgroup. Although both the VI and non-VI groups showed increased income levels over 5 years, the degree of income increase in the VI group was relatively lower than that in the non-VI group. This finding was prominent in the middle-age subgroup. These results strongly suggested that VI induced an income inequality.

Incidence and Risk Factors for Blindness in Uveitis: A Nationwide Cohort Study from 2002 to 2013

Purpose: To investigate the incidence and risk factors of blindness in uveitis.Methods: From a national sample cohort (n = 1,025,340), we selected 9,036 new-onset uveitis patients. Incidences of unilateral and bilateral blindness (visual acuities ≤20/400) were estimated and socioeconomic and clinical risk factors for unilateral blindness in uveitis patients were identified.Result: Incidence of unilateral and bilateral blindness was 2.93 and 0.42 per 1,000 person-years, respectively. The risk factors for unilateral blindness were age >40 (hazard ratio [HR], 2.77, 95% CI [confidence interval], 1.11-6.92) and low household income (HR, 1.50; 95% CI, 1.02-1.98) in uveitis overall, and Behçet's disease (HR, 4.49; 95% CI, 1.59-12.71) in non-anterior uveitis, respectively.Conclusions: Low household income and Behçet's disease influence the risk of blindness in uveitis patients. These findings will help in assessing blindness-related socioeconomic burdens and planning health-care strategies for uveitis patients.

Open globe injuries: Epidemiology, visual and surgical predictive variables, prognostic models, and economic cost analysis

BACKGROUND

Open globe injuries (OGI) represent a visually and economically devastating cause of vision loss. We examined the epidemiology, predictive variables, prognostic models, and economic cost of surgically managed OGI.

METHODS

A retrospective tertiary centre study from 2008 to 2018 of 155 consecutive OGI in individuals aged 16 and older was performed. Medical records review, application of Ocular Trauma Score (OTS) and Classification and Regression Tree Analysis (CART) and cost analysis were undertaken. Key outcomes measured were visual acuity, number of operating theatre visits, prognostication using OTS and CART and estimated costs.

RESULTS

Younger males at work with inadequate protective eyewear (89.1%) and falls in the elderly were overrepresented. Inferior visual outcomes were associated with a more severe OTS score, a larger injury zone, increasing age, the presence of retinal detachment, extraocular muscle involvement, intraocular foreign body, and globe rupture (R²  = 0.723, p < 0.001). Multiple operating theatre visits were required in the presence of retinal detachment, lens or orbit involvement, work-related injury, globe rupture, and a history of previous intraocular surgery (R²  = 0.0423, p < 0.001). Both OTS and CART prognosticated outcomes (p < 0.001). The OTS predicted for no vision (no light perception/enucleation/evisceration) and profound visual loss (worse than 6/120; specificity: both 100%, sensitivity: 88.2% and 88%) whereas the CART predicted for visual survival (light perception or better) and minimal-to-severe visual loss (6/120 or better; specificity: 88.5% and 81.7% , sensitivity: 97.7% and 100%). Estimated annual OGI cost for Australia was AUD48.1-60.5 million (USD37.3-47.0 million).

CONCLUSIONS

The total cost of OGI is immense with young males and the elderly being disproportionately affected. Implementation of targeted government legislation and public health preventative measures may be cost-effective in ameliorating the significant burden.

Inter-regional trends in causes of childhood blindness and low vision in Ghana

BACKGROUND

Inter-regional trends of visual loss in most developing countries remain largely unknown. We compared the causes of childhood blindness among children attending blind schools in the northern (one school) and southern (two schools) regions of Ghana and assessed their need for spectacles and low-vision devices.

METHODS

Using a standardised methodology, children were examined by an ophthalmologist and optometrists in each location. Causes of visual loss were classified anatomically and by time of onset, and avoidable causes identified. Children identified with functional low vision were assessed and provided with low-vision devices.

RESULTS

A total of 252 children under 16 years of age were examined in the schools. The overall prevalence of total blindness was 73 (29.0 per cent), with similar proportions (p = 0.87) in the north (29 [28.4 per cent]) and south (44 [29.3 per cent]); 92 (36.5 per cent) had functional low vision. Two children improved with spectacles and 35 benefited from low-vision devices. Corneal scarring was significantly (p = 0.045) more prevalent in southern Ghana (n = 150) than in the north (n = 102), responsible for visual loss in 36 (24.0 per cent, 95% CI 17.2-30.8 per cent) and 14 (13.7 per cent, 95% CI 7.0-20.4 per cent) cases, respectively. No significant difference (p = 0.321) was observed in the prevalence of cataract between northern (28: 27.5 per cent, 95% CI 18.3-36.2 per cent) and southern Ghana (33: 22.0 per cent, 95% CI 15.4-28.6 per cent). Over 87 per cent of children had 'avoidable' causes of visual loss, with a higher proportion being treatable (124: 49.2 per cent) than preventable (96: 38 per cent).

CONCLUSION

Cataract was the major cause of visual loss in the overall population. The south had a higher proportion of corneal scarring and late-onset blindness compared with the north. More than one-third of blindness in blind schools in Ghana could have been prevented by primary care interventions and nearly half could have been treated surgically to prevent visual loss. Two in five children in blind schools in Ghana could benefit from optical intervention.

The association between socioeconomic status and visual disability among older adults in China

AIM

To investigate the association between socioeconomic status (SES) and visual disability (VD) among older Chinese adults.

METHODS

We obtained data from the Second National Sample Survey on Disability, conducted in China in 2006. A total number of 192 375 older adults (aged≥65y) were screened for suspected VD via interviews with trained examiners. Those who screened positively for VD were referred to ophthalmologists to obtain a final diagnosis.

RESULTS

VD was prevalent among 7.29% of Chinese adults aged 65 and older, and was higher in rural areas (8.71%) than in urban areas (4.82%). After adjusting for SES indicators and covariates, we found that less-educated older adults were more likely to suffer from VD, with an odds ratio (OR) of 2.50 (95%CI: 2.26-2.82) for illiterates, compared with those who graduated from senior high school or above. Older adults who were in the lowest income quintile were more at risk of VD, with an OR of 1.81 (95%CI: 1.68-2.95), compared with adults in the highest income quintile. In urban areas, when compared with adults who graduated from senior high school or above, those who did not continue their education after junior high school, primary school, or those who were illiterate, were more likely to suffer from VD, with an OR of 1.35 (95%CI: 1.51-1.59), 1.84 (95%CI: 1.60-2.12), and 2.63 (95%CI: 2.27-3.04), respectively. Lower levels of income were statistically significant when associated with VD. In rural areas, adults who were illiterate had an OR of 2.21 (95%CI: 1.75-2.79) when compared to adults with senior high school or above education level. Per capita, household income remained significantly associated with VD. Older adults who were ≥85, female, single, and residing in rural areas were associated with higher risks of VD.

CONCLUSION

Individual-level SES among the elderly, in the form of education and income, is associated with VD among elderly Chinese adults in both urban and rural areas; however, the association is stronger in rural areas. Further studies are still required to explore the mechanism behind the relationships.

Assessment of Horizontal Inequity in Eye Care Utilization in the Iranian Middle-aged Population

PURPOSE

The present study was designed to determine the extent that horizontal inequity was realized regarding eye care utilization in a middle-aged population as well as factors affecting this equity.

METHODS

Data were obtained from a population-based study (Shahroud Eye Cohort Study) in 2009 that included 5190 participants from 40 to 64 years of age. Horizontal inequity was determined based on the following variables: (i) economic status, (ii) eye care service needs, (iii) non-need variables, and (iv) eye care utilization (visiting an ophthalmologist or optometrist). Decomposition analysis of the concentration index based on a nonlinear model and indirect standardization was used to ascertain the contribution of each factor in inequity of eye care utilization.

RESULTS

After adjusting for need variables, the results of our study demonstrated that horizontal inequity in eye care utilization in a middle-aged Iranian population remained positive and significant (horizontal inequity: 0.19; 95% confidence interval: 0.17-0.23) indicating that use of services was focused among participants with a better financial situation. Furthermore, decomposition analysis demonstrated that educational level and economic status had the greatest contribution (54.1% and 41.1%, respectively) in comparison to other variables.

CONCLUSION

This study demonstrated that horizontal inequity exists in eye care utilization among the middle-aged Iranian population.

Multiple deprivation, vision loss, and ophthalmic disease in adults: global perspectives

The association between socioeconomic position and morbidity and mortality has long been recognized. We evaluate the evidence for an association between multiple aspects of deprivation and ocular health in a global context. This is a systematic review of studies that evaluated deprivation in the adult population in the context of the major acquired causes of visual loss such as cataract, diabetic eye disease, glaucoma, age-related macular degeneration, and ocular trauma. The search strategy identified relevant studies reported between 1946 and August 2016, with randomized control trials, case-control, cohort, and cross-sectional study designs being selected for inclusion. The studies identified in this review from across the world demonstrate the extent to which the common themes such as low educational attainment and low income may be associated with increased incidence of various sight-threatening conditions and may adversely affect access to specialist assessment and delivery of treatment. Health inequality may always persist, but an increased recognition of the importance of the various impacts of deprivation may empower policy makers to target limited resources to the most vulnerable groups in order to deliver the greatest benefit.

Quality of Life and Psychological Aspects in Patients with Visual Impairment Secondary to Uveitis: A Clinical Study in a Tertiary Care Hospital in Brazil

PURPOSE

To evaluate the quality of life in individuals with bilateral visual impairment secondary to uveitis and its association with sociodemographic, clinical and psychosocial aspects.

METHODS

Data were collected through a structured interviews, using four forms; the SF-12v2, HADS, NEI-VFQ-25 and a specific form developed to collect clinical and sociodemographic data.

RESULTS

80 patients were included with a mean age of 42.8 years; 63.8% female; 57.5% with permanent reduction of familiar income. The average number of medical visits was 15.2 ±10.7/year. In terms of health-related quality of life (HRQol), the mean of VFQ-25 score was 36.6 ± 15.1 and the mean of SF-12 physical and mental components scores were 43.3 ± 9.9 and 44.9 ± 12.2. Anxiety and depression symptoms were found in 65.1% and 32.5% of patients, respectively.

CONCLUSIONS

Visual impairment has impact on several scales of HRQoL leading to productivity loss and consumption of health resources.

Prospective Study of Eye Disease in Timor-Leste: The East Timor Eye Program

PURPOSE

This study aimed to present the methodology of the East Timor Eye Program and report the prevalence of eye disease seen at the National Eye Centre during a 3-month sample period between June and August 2012.

DESIGN

Two hundred ninety-three new patients aged 17 years or older were assessed at the National Eye Centre in Dili, Timor-Leste.

METHODS

All participants received a comprehensive dilated eye examination that included distance visual acuity measurements, indirect fundoscopy, and a complete slit lamp assessment including gonioscopy and intraocular pressure measurement. Each patient completed an interview-administered general questionnaire, and information on general health, ocular history, and medication was obtained. Anthropometric measurements were also taken and recorded.

RESULTS

A total of 293 patients, 183 males (62.5%) and 110 females (37.5%), aged between 17 and 88 years (mean, 47.66 years) were recruited and examined. The 3 most common clinical eye presentations were conjunctival disorders (60.41%), followed by lens disorders (48.12%) and scleral, corneal, iris, and ciliary body disorders (46.42%). The 3 most common conditions causing blindness (visual acuity less than 3/60 as defined by the World Health Organization) were lens disorders (45.9%), choroidal and retinal disorders (18.9%), and other disorders of the eye and adnexa (13.5%).

CONCLUSIONS

The East Timor Eye Program is an effective program that has enabled the management and treatment of various eye conditions in residents of Timor-Leste. The program set high standards for stringent and accurate data collection and ophthalmic diagnoses in a low-resource setting. Lens disorders and choroidal and retinal disorders were the most common conditions causing blindness.

The prevalence of self-reported vision difficulty in economically disadvantaged regions of South Africa

Background

Vision impairment, resulting in vision difficulties, is a leading cause of disability, and hence one of the key barriers for people to access education and employment, which may force them into poverty.

Objectives

The objective of this study was to determine the prevalence of self-reported vision difficulties as an indicator of vision impairment in economically disadvantaged regions in South Africa, and to examine the relationship between self-reported vision difficulties and socio-economic markers of poverty, namely, income, education and health service needs.

Methods

A cross-sectional study was conducted in economically disadvantaged districts to collect data from households on poverty and health, including vision difficulty. As visual acuity measurements were not conducted, the researchers used the term vision difficulty as an indicator of vision impairment. Data were collected from 27 districts (74 901 respondents). Logistic regression analysis and chi-square tests were used to determine bivariate relationships between variables and self-reported vision difficulty. Kernel density estimators were used for age, categorised by self-reported and not reported vision difficulty.

Results

Prevalence of self-reported vision difficulty was 11.2% (95% CI, 8.7% – 13.7%). More women (12.7%) compared to men (9.5%) self-reported vision difficulty (p < 0.01). Self-reported vision difficulty was higher (14.2%) for respondents that do not spend any money. A statistically significant relationship was found between the highest level of education and self-reporting of vision difficulty; as completed highest level of education increased, self-reporting of vision difficulty became lower (p < 0.01). A significantly higher prevalence of self-reported vision difficulty was found in respondents who are employed (p < 0.01), 17% (95% CI: 12.8% – 21.1%).

Conclusion

The evidence from this study suggests associations between socio-economic factors and vision difficulties that have a two-fold relationship (some factors such as education, and access to eye health services are associated with vision difficulty whilst vision difficulty may trap people in their current poverty or deepen their poverty status). The results are thus indicative of the need for further research in South Africa.

Barriers to use of refractive services in Mozambique

PURPOSE

Uncorrected refractive error remains a leading cause of visual impairment (VI) across the globe with Mozambique being no exception. The establishment of an optometry profession in Mozambique that is integrated into the public health system denotes significant progress with refractive services becoming available to the population. As the foundations of a comprehensive refractive service have now been established, this article seeks to understand what barriers may limit their uptake by the general population and inform decision making on improved service delivery.

METHODS

A community-based cross-sectional study using two-stage cluster sampling was conducted. Participants with VI were asked to identify barriers that were reflective of their experiences and perceptions of accessing refractive services. A total of 4601 participants were enumerated from 76 clusters in Nampula, Mozambique.

RESULTS

A total of 1087 visually impaired participants were identified (884 with near and 203 with distance impairment). Cost was the most frequently cited barrier, identified by more than one in every two participants (53%). Other barriers identified included lack of felt need (20%), distance to travel (15%), and lack of awareness (13%). In general, no significant influence of sex or type of VI on barrier selection was found. Location had a significant impact on the selection of several barriers. Pearson χ analysis indicated that participants from rural areas were found to feel disadvantaged regarding the distance to services (p ≤ 0.001) and adequacy of hospital services (p = 0.001).

CONCLUSIONS

For a comprehensive public sector refractive service to be successful in Mozambique, those planning its implementation must consider cost and affordability. A clear strategy for overcoming lack of felt need will also be needed, possibly in the form of improved advocacy and health promotion. The delivery of refractive services in more remote rural areas merits careful and comprehensive consideration.

Economic inequality in eye care utilization and its determinants: a Blinder-Oaxaca decomposition

BACKGROUND

The current study aimed to determine eye care utilization, to assess the role of economic inequality in the utilization of eye care services, and to identify its determinants in Shahroud, North of Iran.

METHODS

Of the 6,311 invited people, 5,190 (82.24%) individuals aged 40 to 64 years old participated in the study. A history of a visit by an ophthalmologist or optometrist was considered as eye care utilization. The gap between low- and high-economic groups was decomposed into its determinants using the Oaxaca decomposition method.

RESULTS

Among the participants, 16.32% [95% Confidence Intervals (CI)= 15.31-17.33%] had never been examined by an ophthalmologist or optometrist, and 30.94% (95% CI= 29.69-32.20%) had not undergone an eye examination in the past 5 years. This negative history was significantly higher among female subjects [Odds Ratio (OR)= 1.79, 95% CI= 1.51-2.14], the low-economic group (OR= 2.33, 95% CI= 1.90-2.87), the visually impaired (OR= 1.41, 95% CI= 1.05-1.90), and the uninsured (OR= 1.93, 95% CI= 1.45-2.58). The negative history of eye examination decreased with increasing in age (OR= 0.94, 95% CI= 0.93-0.96) and education (OR= 0.94, 95% CI= 0.92-0.96). In this study, 24.72% (95% CI= 22.30-27.14) of the low-economic group and 9.94% (95% CI= 8.75-11.14) of the high-economic group had no history of eye examination. Decomposition of the gap between the two economic groups showed that education and gender were the most important determinants of inequality.

CONCLUSION

A considerable percentage of adults, even those with visual impairment, do not receive appropriate eye care. There is a definite economic inequality in the community for which poverty per se could be the major cause.

Physiology and psychology of vision and its disorders: a review

The purpose of this review is to bring together to the physiology and psychology of vision and to analyze, based on our own data and on the available literature, the relationship between sight loss and individual reactions. As recent treatments for depression are often effective and have few side-effects, ophthalmologists should consider referral for treatment of depression in patients suffering from vision impairment. For this reason, vision rehabilitation should be more readily available and recommended.

Area deprivation, individual socioeconomic status and low vision in the EPIC-Norfolk Eye Study

Background

Poor vision is associated with lower socioeconomic status, but less is known about its relationship to area deprivation.

Methods

The European Prospective Investigation into Cancer and Nutrition study Norfolk Eye Study was a cross-sectional study of 8563 participants with completed eye examinations. Logarithm of the minimum angle of resolution (logMAR) visual acuity (VA) was measured using standard protocols and low vision (LV) was defined as Snellen equivalent (VA) ≤6/12 in the better eye. Uncorrected refractive error (URE) was defined as improvement of VA by 2 logarithm of the minimum angle of resolution lines with pinhole. The lowest 5% of index of multiple deprivation rank was used to define the most deprived areas. The index of multiple deprivation is a composite measure using routine data from seven domains of deprivation to identify the most disadvantaged areas in England. Logistic regression was used to examine univariable and multivariable associations with LV.

Results

Ninety-six participants with missing data were excluded, leaving 8467 for analysis (98.9%). The mean age of the study group was 68.7 years (SD=8.1, range=48–92), with 55.1% women. LV was present in 263 participants (3.1%, 95% CI 2.7 to 3.5%). LV was associated with deprivation after adjusting for age, sex, education, social class and cataract surgery (OR=1.7, 95% CI 1.1 to 2.6, p=0.03), but this effect was mitigated by additionally adjusting for URE (OR=1.5, 95% CI 1.0 to 2.4, p=0.09).

Conclusions

People with LV are more likely to live in the most deprived areas; this association was independent of socioeconomic status and partly mediated by URE. Targeting URE in deprived areas may reduce health inequalities associated with LV.

Visual impairment and blindness in spanish adults: geographic inequalities are not explained by age or education

OBJECTIVES

The objectives of this study were to examine for the first time the prevalence of visual impairment and blindness among adults in Spain, to explore regional differences, and to assess whether they may vary as a function of sex or be explained by age and individual or regional socioeconomic position.

DESIGN

Data were obtained from the 2008 Spanish Survey on Disability, Personal Autonomy, and Dependency Situations, a cross-sectional survey based on a representative sample of the noninstitutionalized population of Spain.

PARTICIPANTS

The sample was composed of 213 626 participants aged ≥15 years (103 093 men and 110 533 women); 360 were blind (160 men and 200 women), 4048 had near visual impairment (1397 men and 2651 women), and 4034 had distance visual impairment (1445 men and 2589 women).

METHODS

The prevalence of near and distance visual impairment was calculated for each region. Multiple logistic regression models were fitted to calculate odds ratios and 95% confidence intervals. All analyses were stratified by sex.

MAIN OUTCOME MEASURES

Visual impairment was based on 3 questions aimed at identifying blindness and near and distance visual impairment.

RESULTS

The prevalence (percentage) of blindness was 0.17 (men, 0.16; women, 0.18): 1.89 for near visual impairment (men, 1.36; women, 2.40), 1.89 for distance visual impairment (men, 1.40; women, 2.34), and 2.43 for any visual impairment (men, 1.81; women, 3.02). Regional inequalities in the prevalence of visual impairment were observed, correlated with regional income, and the prevalence was consistently higher among women than men. The magnitude of the inequalities remained after adjusting for age and educational level, and a north-to-south pattern of increasing prevalence was observed.

CONCLUSIONS

Regional and sex inequalities in the prevalence of visual impairment and blindness were observed in Spain, with a north-to-south gradient of increasing prevalence that was not explained by age or individual educational level but was correlated with regional level of economic development. Factors that could be prioritized for future policies and research include differential regional economic development, rural environment, quality of eye care services, diabetes, ultraviolet light exposure, or gender inequalities in diagnostic and therapeutic health care.

Economic inequality in presenting near vision acuity in a middle-aged population: a Blinder-Oaxaca decomposition

PURPOSE

To investigate economic inequality and its determinants in near vision, in a middle-aged population.

METHODS

In this population-based study, the presenting near vision in the better eye was investigated as the main outcome. If this vision revealed a value ≥1.6 M, the participant was considered to have presenting near vision impairment (PNVI). The effect of variables studied on PNVI was investigated using logistic regression. Economic inequality in PNVI was investigated using the Oaxaca-Blinder decomposition method.

RESULTS

PNVI in the better eye was observed in 18.2% (95% CI 16.8 to 19.6) of participants. The prevalence of PNVI in the high and low economic groups was 11.7% (95% CI 10.3 to 13.0) and 28.5% (95% CI 26.0 to 31.0), respectively. Age and education were observed as the main factors in the explained portion of this gap and were in favour of the high economic group. Gender and eye care utilisation were factors affecting the unexplained portion of this gap and were in favour of the low economic group.

CONCLUSIONS

Economic inequality plays a significant role in PNVI, while age and education are among the main factors affecting this gap. The effect caused by any change in these two factors was found to have a greater effect on women with low economic status.

Social inequalities in blindness and visual impairment: a review of social determinants

Health inequities are related to social determinants based on gender, socioeconomic status, ethnicity, race, living in a specific geographic region, or having a specific health condition. Such inequities were reviewed for blindness and visual impairment by searching for studies on the subject in PubMed from 2000 to 2011 in the English and Spanish languages. The goal of this article is to provide a current review in understanding how inequities based specifically on the aforementioned social determinants on health influence the prevalence of visual impairment and blindness. With regards to gender inequality, women have a higher prevalence of visual impairment and blindness, which cannot be only reasoned based on age or access to service. Socioeconomic status measured as higher income, higher educational status, or non-manual occupational social class was inversely associated with prevalence of blindness or visual impairment. Ethnicity and race were associated with visual impairment and blindness, although there is general confusion over this socioeconomic position determinant. Geographic inequalities and visual impairment were related to income (of the region, nation or continent), living in a rural area, and an association with socioeconomic and political context was suggested. While inequalities related to blindness and visual impairment have rarely been specifically addressed in research, there is still evidence of the association of social determinants and prevalence of blindness and visual impairment. Additional research should be done on the associations with intermediary determinants and socioeconomic and political context.

Antioxidants in Prevention of Cataracts in South India: Methodology and Baseline Data

PURPOSE

To describe the methodology and baseline data for the Antioxidants in Prevention of Cataracts (APC) study in South India.

METHODS

The APC study is a prospective, 5-year, randomized, triple-masked, placebo-controlled, field-based clinical trial to examine the effect of antioxidants (combination tablet of vitamins A, C, and E) on progression of cataract. The primary outcome variable is cataract progression (nuclear opalescence), evaluated with the slit-lamp biomicroscope by the Lens Opacification Classification System III method. Secondary outcome variables are progression in cortical and posterior subcapsular opacity and nuclear color, change in best corrected visual acuity, myopic shift, and treatment failure (progression to cataract surgery or best corrected vision worse than 20/400 in an eye). Inclusion criteria are age between 35 and 50 years and best-corrected visual acuity of 20/40 or better. Exclusion criteria are a diagnosis of diabetes mellitus or nonfasting blood glucose level>7.8 mmol/L, history or presence of various ocular conditions or treatment forms, or current use of vitamin supplements. Baseline ophthalmic, demographic, and potential cataract risk factor data (such as smoking, sunlight, or alcohol exposure) were compared between groups on an intent-to-treat basis.

RESULTS

Of 954 people screened, 798 were enrolled, a sample size which exceeded the required estimate. More than 80% of subjects had 20/20 or better vision in at least one eye, and baseline prevalence of significant cataract according to the LOCS III grading scale was high. The two treatment groups were comparable for all baseline measures except alcohol intake.

CONCLUSION

The sample size and group baseline characteristics will provide sufficient power to detect a change in cataract progression within 5 years.

Visual impairment from age-related cataract among an indigenous African population

AIM

To determine the magnitude of visual impairment (VI) resulting from lens opacity/cataract among a rural population in southwestern Nigeria.

METHOD

A population-based cross-sectional survey using a multistage sampling method to select subjects >or=50 years. Participants with pinhole visual acuity of <or=6/18 in their better eye, exclusively from lens opacity/cataract, were further examined by an ophthalmologist. Their level of VI was categorised using the International Classification of Disease tenth revision and lens opacity was graded using the World Health Organization's cataract grading system.

RESULTS

From the enumerated population of 1200 subjects, 1031 subjects were examined. The prevalence of VI from cataract/lens opacity in the population studied was 11.9% (95% CI: 10.1-14.0) with a cataract blindness prevalence of 2.0% (95% CI: 1.3-3.0). The odds for VI increased with increasing age and female patients had 1.6 times the odds for cataract blindness than did male patients. Mixed cataract was the most prevalent of the visually disabling cataract. (3.9% (95% CI: 2.8-5.2)), whereas posterior subcapsular cataract was the least prevalent (2.5% (95% CI: 1.7-3.7)).

CONCLUSION

VI from cataract remains a public health problem in the Akinyele district of Nigeria. The need for a comprehensive cataract surgical service using the VISION 2020 model is necessary in the district if the burden from the backlog of visually disabling cataract is to be reduced.

Biological diversity, dietary diversity, and eye health in developing country populations: establishing the evidence-base

Human and ecosystem health converge around biological diversity issues. Cultivated and wild plants as food and medicine make essential contributions to human health, which in turn provides rationales for conservation. While wild and cultivated plant diversity reasonably facilitates dietary diversity and positive health outcomes, the challenges of demonstrating this relationship limit its impact in concept, policy, and practice. We present a rationale for testing the dietary contribution of biological diversity to improved eye health as a case study based on existing phytochemical, pharmacological, and clinical knowledge. We consider the empirical evidence needed to substantiate, interpret, and apply this relationship at a population and ecosystem level within a unified research framework. Epidemiological data strongly support the prevention of childhood vitamin A deficiency blindness, cataract, and age-related macular degeneration by fruit and vegetable consumption. Phytonutrients, including the carotenoids lutein and zeaxanthin, protect the eye from oxidative stress and harmful light exposure. Laboratory, community, and population level research should prioritize food composition of dietary plants from both agriculture and the wild. Intervention studies, focus groups, and transmission of knowledge of local species and varieties within communities will further interpretation of epidemiological data. Population-based studies combining clinical data and measures of access and consumption of biological diversity are key to demonstrating the important relationships among biodiversity, dietary diversity, and health outcomes.

A novel method of notification to profile childhood visual impairment in Scotland to meet the needs of children with visual impairment

The purpose of this study is to pilot a new notification system for children with visual impairment (VI) and describe the initial summary findings. A system of notification of children in Scotland with VI was established. Information concerning this system was distributed to professionals working with visually impaired children to forward to parents. Parents, teachers and health professionals were all encouraged to notify children with VI. 975 families with children with (VI) were notified and received information and support from Visual Impairment Scotland (VIS). For this review, the data from 850 parents were included in the analysis. The provision of a range of support services for parents and children with VI has led to a wide range of children being notified to VIS. The causes of VI can be recorded as well as other useful demographic information. The methods used could be applied across the range of low incidence childhood disabilities.

Blindness and poverty in India: the way forward

A few recent studies have shown that poverty is an exacerbating and often determining factor in the incidence of disabling conditions, including visual impairment. Recent estimates from the World Health Organization indicate that 90 per cent of all those affected by visual impairment live in the poorest countries of the world. India is home to one-fifth of the world's visually impaired people and therefore, any strategies to combat avoidable blindness must take into account the socio-economic conditions within which people live. This paper looks at the relationship between poverty and blindness in India and suggests strategies to address blindness prevention in a comprehensive manner.

Poverty and blindness in Africa

Africa carries a disproportionate responsibility in terms of blindness and visual impairment. With approximately 10 per cent of the world's population, Africa has 19 per cent of the world's blindness. It is no surprise that this reality also mirrors the situation in terms of the burden of world poverty. There is an increasing recognition of the need to highlight the link between poverty, development and health care. Blindness, disabling visual impairment and the overall lack of eye-care services are too often the result of social, economic and developmental challenges of the developing world. The state of eye care in Africa stands in alarming contrast to that in the rest of the world. Poor practitioner-to-patient ratios, absence of eye-care personnel, inadequate facilities, poor state funding and a lack of educational programs are the hallmarks of eye care in Africa, with preventable and treatable conditions being the leading cause of blindness. Eye diseases causing preventable blindness are often the result of a combination of factors such as poverty, lack of education and inadequate health-care services. The challenge that Vision 2020 has set itself in Africa is enormous. Africa is not a homogenous entity, the inter- and intra-country differences in economic development, prevalence of disease, delivery infrastructure and human resources amplify the challenges of meeting eye-care needs. The successful implementation of Vision 2020 programs will be hindered without the development of a comprehensive, co-ordinated strategy that is cognisant of the differences that exist and the need for comprehensive solutions that are rooted in the economic and political realities of the continent as well as the individual countries and regions within countries. This strategy should recognise the need for economic growth that results in greater state funded eye-care services that focus on health promotion to ensure the prevention of eye disease, the development of eye clinics in hospitals and health clinics, and the training of the appropriate human resources.

Prevalence and causes of blindness and low vision in Timor-Leste

AIM

To estimate the prevalence and causes of blindness and low vision in people aged > or = 40 years in Timor-Leste.

METHOD

A population-based cross-sectional survey using multistage cluster random sampling to identify 50 clusters of 30 people. A cause of vision loss was determined for each eye presenting with visual acuity worse than 6/18.

RESULTS

Of 1470 people enumerated, 1414 (96.2%) were examined. The age, gender and domicile-adjusted prevalence of functional blindness (presenting vision worse than 6/60 in the better eye) was 7.4% (95% CI 6.1 to 8.8), and for blindness at 3/60 was 4.1% (95% CI 3.1 to 5.1). The adjusted prevalence for low vision (better eye presenting vision of 6/60 or better, but worse than 6/18) was 17.7% (95% CI 15.7 to 19.7). Gender was not a risk factor for blindness or low vision, but increasing age, illiteracy, subsistence farming, unemployment and rural domicile were risk factors for both. Cataract was the commonest cause of blindness (72.9%) and an important cause of low vision (17.8%). Uncorrected refractive error caused 81.3% of low vision.

CONCLUSION

Strategies that make good-quality cataract and refractive error services available, affordable and accessible, especially in rural areas, will have the greatest impact on vision impairment.

Eye disease and care at hospital clinics in Cook Islands, Fiji, Samoa and Tonga

PURPOSE

To obtain eye disease and care data to assist with service planning in Cook Islands, Fiji, Samoa and Tonga.

METHODS

A hospital-based rapid assessment including interviews and examination of clinical records.

RESULTS

An overview of equipment, staff and services was attained. Visual impairment was associated with increasing age but not gender of clinic attendees. Cataract was the most common cause of low vision and blindness. A substantial proportion of visually significant cataract, particularly that causing low vision but not blindness, was not offered treatment. The vision outcome of cataract surgery in Fiji was less successful than elsewhere. Only Samoa achieved the World Health Organization suggested outcomes. Refractive error was a significant cause of low vision, but poorly treated. Diabetic retinopathy was a substantial contributor to visual impairment at all locations except the Cook Islands, but not all was treated with laser. Trauma/corneal opacity was an important cause of blindness in Cook Islands and Tonga. Pterygium-induced low vision and glaucoma blindness were diagnosed most frequently in Samoa.

DISCUSSION

This methodology enabled quick and cost-efficient collection of data about hospital eye services, the conditions diagnosed and treated, and the outcome of treatment. It could easily be repeated by local clinicians to measure the impact of service planning and implementation. In the four countries audited, the management of, and intervention outcomes for, cataract, refractive error, diabetic retinopathy and trauma need attention.

Direct costs of blindness experienced by patients enrolled in managed care

PURPOSE

To evaluate total and condition-related charges incurred by blind patients in a managed care population in the United States and compare total charges with those of a matched nonblind cohort.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients with blindness (N = 10 796) and a 1:1 matched cohort of nonblind patients were selected from a managed care claims database. All study subjects were required to be > or =18 years old at diagnosis (blind patients) or enrollment (nonblind patients) and to have had > or =1 years of continuous follow-up.

METHODS

Total and pharmacy-related direct medical charges in the first year of follow-up were calculated for both blind and nonblind cohorts. Among blind patients, condition-related charges, charge per treated person, and charge breakdown by age group were calculated. For patients with follow-up extending past 1 year, total charges (both cohorts) and condition-related charges (blind cohort only) were assessed and annualized. Mean and median charges were assessed for blind and nonblind patients within each stratum of matched covariates; a multivariate linear regression assessed the statistical significance of the difference in charges between the 2 cohorts.

MAIN OUTCOME MEASURES

Total health care charges in the first year of follow-up and condition-related health care charges in the first year of follow-up for blind patients.

RESULTS

For the blind population (mean age, 52 years [standard deviation (SD), 17.5]), the total mean and median health care charges per person in the first year were $20,677 (SD, $48,835) and $6854, respectively. Total mean and median health care charges per nonblind patient in the first year were $13,321 (SD, $40,059) and $3778, respectively. Condition-related charges among blind patients were substantially lower than total charges, with mean and median charges per person of $4565 (SD, $17,472) and $371, respectively. After adjusting for covariates, blind patients had significantly higher total health care charges in the first year of follow-up than nonblind patients (P<0.0001). Costs of the blind did not differ substantially from costs of the normally sighted in subsequent years of follow-up.

CONCLUSION

This study demonstrates the substantial direct cost burden of blindness during the first year of follow-up in a managed care population.

Socioeconomic status, systolic blood pressure and intraocular pressure: the Tanjong Pagar Study

BACKGROUND

Lower socioeconomic status (SES) is associated with higher morbidity and mortality in many countries. Present evidence suggests that glaucoma has similar risk factors to major chronic diseases such as cardiovascular disease. This study investigates the association between SES and intraocular pressure (IOP), an important risk factor for glaucoma.

METHODS

The Tanjong Pagar Study was a population-based cross-sectional survey of Chinese people aged 40-79 years, who were randomly selected from the Singapore electoral register. Of the 2000 people selected, 1717 were considered eligible and 1090 were examined in clinic and included in the present study. IOP was measured using applanation tonometry. SES was assessed using a standardised questionnaire; education and income were used as the main explanatory variables. The effect of systolic blood pressure (SBP) was also examined.

RESULTS

Participants with lower levels of education and income had higher mean IOP (both p<0.01). These associations remained after adjusting for age and central corneal thickness, a strong independent predictor. SBP was strongly associated with both SES and IOP (both p<0.01). Adjusting for SBP attenuated the association between SES and IOP.

CONCLUSION

Participants with lower education and income have a higher mean IOP. This effect may be mediated, in part, by an association of education and income with SBP. This is the first study to suggest that there is a social gradient in the distribution of the only major modifiable risk factor for glaucoma. Increasing similarities exist between the causation models of chronic diseases and that of glaucoma.

The Antioxidants in Prevention of Cataracts Study: effects of antioxidant supplements on cataract progression in South India

AIM

To determine if antioxidant supplements (beta carotene and vitamins C and E) can decrease the progression of cataract in rural South India.

METHODS

The Antioxidants in Prevention of Cataracts (APC) Study was a 5 year, randomised, triple masked, placebo controlled, field based clinical trial to assess the ability of interventional antioxidant supplements to slow cataract progression. The primary outcome variable was change in nuclear opalescence over time. Secondary outcome variables were cortical and posterior subcapsular opacities and nuclear colour changes; best corrected visual acuity change; myopic shift; and failure of treatment. Annual examinations were performed for each subject by three examiners, in a masked fashion. Multivariate modelling using a general estimating equation was used for analysis of results, correcting for multiple measurements over time.

RESULTS

Initial enrolment was 798 subjects. Treatment groups were comparable at baseline. There was high compliance with follow up and study medications. There was progression in cataracts. There was no significant difference between placebo and active treatment groups for either the primary or secondary outcome variables.

CONCLUSION

Antioxidant supplementation with beta carotene, vitamins C and E did not affect cataract progression in a population with a high prevalence of cataract whose diet is generally deficient in antioxidants.

Prevalence of trachoma and diabetes-related eye disease among a cohort of adult Aboriginal patients screened over the period 1999-2004 in remote South Australia

BACKGROUND

To determine the prevalence of trachoma and diabetes-related eye disease within the adult Aboriginal population screened by the South Australian Eye Health Program between 1999 and 2004 inclusive.

METHODS

The South Australian Eye Health Program visited 22 Aboriginal communities in remote South Australia. Visiting ophthalmologists and optometrists systematically collected data on the cohort of adult patients seen over the period 1999-2004. Prevalence and grade of trachoma according to World Health Organization classification and the prevalence and degree of diabetic retinopathy according to the Early Treatment Diabetic Retinopathy Study and National Health and Medical Research Council guidelines were recorded.

RESULTS

A population of 1651 Aboriginal patients was examined. Sixty-two per cent were female and 38% were male. Twenty patients (1.2%) had evidence of active trachoma with 260 (15.7%) patients having either lid scarring, trichiasis or corneal opacity. There was no significant association between gender and the prevalence of trachoma (P = 0.48). Seven hundred and seventy-one patients within the examined population had diabetes mellitus (46.70%). Significantly more women than men were affected and prevalence increased with age (P < 0.0001). One hundred and sixty-nine patients (22%) with diabetes mellitus had features of diabetic retinopathy, and of these patients 77 had background diabetic retinopathy (46%) and 92 (54%) had either proliferative diabetic retinopathy or maculopathy. Prevalence of clinically significant macula oedema among those with maculopathy (14 of 50 patients) was 28%.

CONCLUSIONS

The data suggest that although trachoma is still endemic in this South Australian Aboriginal population the prevalence and severity are less than previously reported. Diabetes mellitus has a high prevalence within this population and great potential for detrimental visual sequelae.

Socioeconomic differences in glaucoma patients' knowledge, need for information and expectations of treatments

PURPOSE

To study the specific items for which socioeconomic differences in glaucoma patients' knowledge, need for information and expectations of treatments exist, with the aim of developing a patient education programme.

METHODS

A total of 44 randomly selected ophthalmologists assigned 166 consecutive outpatient glaucoma patients to complete a questionnaire that had been systematically developed based on focus group interviews, suggestions from several experts and a pilot test. Topics included knowledge about glaucoma and its treatment, need for information and expectations of treatment. Educational level was used as a measure for socioeconomic status. Logistic regression analysis was conducted to adjust for age, sex and duration of glaucoma.

RESULTS

After adjusting for age, sex and duration of glaucoma, knowledge of glaucoma and its treatment was found to be positively correlated with socioeconomic status. Items on knowledge with socioeconomic differences concerned risk factors, pathophysiology and consequences of glaucoma, as well as effects and adverse effects of treatments. The lowest socioeconomic group demonstrated more need for information on public assistance and practical aspects of glaucoma and more often expected that glaucoma damage could be repaired.

CONCLUSION

Important socioeconomic differences in knowledge, need for information and expectations of treatment exist in glaucoma patients. Patient education should focus on every glaucoma patient, but better information for the lower socioeconomic groups about specific items mentioned in this study might reduce the negative effects of low socioeconomic status on visual impairment.

Prevalence of cicatricial trachoma in an indigenous population of Central Australia: the Central Australian Trachomatous Trichiasis Study (CATTS)

BACKGROUND

Trachoma is one of the leading causes of blindness worldwide, resulting from conjunctival scarring, upper lid entropion and trichiasis, leading to corneal scarring and opacification. This study was designed to investigate the current prevalence of cicatricial trachoma in an indigenous population within Central Australia and help determine whether trachoma remains a public health issue.

METHODS

Participants aged 40 and over were recruited from patients attending one of 16 remote ophthalmology clinics held at indigenous communities in Central Australia within the Northern Territory. Once informed consent had been obtained, each patient underwent examination for evidence of trachomatous scarring, trachomatous trichiasis and corneal opacities. Results were collated and compared with previous prevalence surveys.

RESULTS

Among the sample (n = 181), there were 97 patients (54%; 95% CI 46.7-61.3) with trachomatous scarring, 15 patients (8%; 95% CI 2.8-13.2) with trichiasis and 5 patients (3%; 95% CI 0.5-5.5) with corneal opacities.

CONCLUSION

This study suggests that, although the prevalence of the cicatricial and blinding consequences of trachoma may be decreasing in patients aged 40 years or greater, when compared with the current prevalence in other areas of Australia, trachoma still remains a public health issue in Central Australia.

Blinding trachoma: a disease of poverty

Trachoma accounts for 15% of blindness worldwide, affecting the world's poorest communities. How can the disease be controlled?

Incidence of visual loss in rural southwest Uganda

BACKGROUND

Surveys have been conducted to measure prevalence of eye disease in Africa, but not of incidence, which is needed to forecast trends. The incidence of visual loss is reported in southwest Uganda.

METHODS

A rural population residing in 15 neighbouring villages was followed between 1994-5 (R1) and 1997-8 (R2). Survey staff screened adult residents (13 years or older) for visual acuity using laminated Snellen's E optotype cards at each survey. Those who failed (VA >6/18) were evaluated by an ophthalmic clinical officer and an ophthalmologist. Incidence of visual loss (per 1000 person years (PY)) was calculated among those who had normal vision at R1.

RESULTS

2124 people were studied at both survey rounds (60.9% of those screened at R1); 48% were male. Participants in R1 were older (34.7 versus 31.5 years at R2, p<0.001). Visual loss in R2 occurred in 56 (2.8%) of 1997, yielding a crude incidence rate of 9.9, and an age standardised incidence rate of 13.2, per 1000 PY. Incidence of visual loss increased with age from 1.21 per 1000 PY among people aged 13-34 to 64.2 per 1000 PY in those aged 65 years or older (p for trend >0.001). The six commonest causes of visual loss were: cataract, refractive error, macular degeneration, chorioretinitis, glaucoma, and corneal opacity. If similar rates are assumed for the whole of Uganda, it is estimated that 30 348 people would develop bilateral blindness or bilateral visual impairment, per year.

CONCLUSIONS

Cataract and refractive error were the major causes of incident visual loss in south west Uganda. These data are valuable for forecasting and planning eye services.

Vision impairment in the Pacific region

The Western Pacific region is one of great diversity, containing the most populous country, China, and many small Pacific island countries. This review describes the prevalence of blindness and vision loss, illustrates the changing trends in the important causes of vision loss and blindness, and the stages of development of the delivery of eye care services across this region.

Blindness and visual impairment in the Americas and the Caribbean

AIM

To summarise available data on the prevalence and causes of visual impairment and blindness in the Americas and the Caribbean.

METHODS

The published literature was searched in Medline and LILACS using the following key words: blindness, visual impairment, prevalence. Articles were reviewed, and the references of the articles were also searched for relevant articles, which were also reviewed.

RESULTS

Using the mortality in children under the age of 5 as an indicator, the overall prevalence of childhood blindness (in the under age 15 group) for the region was estimated at 0.45/1000, with the majority (67%) living in countries with mortality of children under age 5 above 30/1000 live births. Corneal opacities were more common in countries where the under 5 year mortality are above 30/1000 live births and retinopathy of prematurity (ROP) was an important cause in countries with intermediate death rates. For adults, overall blindness rates were not estimated because of the social, economic, and ethnic diversity in the region. The primary causes of visual loss in adults in the Americas were age related eye diseases, notably cataract and glaucoma in the African-American and Hispanic populations, and age related macular degeneration in the white population. Uncorrected refractive error was a significant cause of decreased vision across ages, ethnic groups, and countries.

CONCLUSION

More data are needed on the magnitude and causes of visual loss for the Caribbean and Latin American countries. Rates of blindness and visual loss from available data within these countries are widely disparate. Prevention and control of avoidable blindness needs to be an ongoing focus in this region.