Prevalence of Refractive Errors in the INK Area, Durban, South Africa.

PURPOSE: To determine the prevalence and types of refractive errors in persons aged 35 years and older in the Inanda, Ntuzuma, and KwaMashu (INK) area of Durban, KwaZulu-Natal Province, South Africa. METHODS: Refractive error data were obtained by autorefraction (Retinomax K-Plus; Nikon, Tokyo, Japan), retinoscopy, and subjective refraction. Refractive error was defined using spherical equivalents as myopia (<-0.5D) and hyperopia (>+0.5D). Astigmatism was defined as cylinder equal to or greater than -0.5D in either eye. RESULTS: Participants' ages ranged from 35 to 90 years, with a mean of 53.05 ± 11.4 years. Women comprised 75% of the subjects. The prevalence of refractive error was 57.3%, with myopia 11.4%, hyperopia 37.7%, and astigmatism 25.7%. Myopia and astigmatism were significantly more prevalent in men (p < 0.01), whereas hyperopia was more prevalent in women (p < 0.01). Hyperopia was significantly associated with education (p < 0.01), whereas myopia and astigmatism were not (p = 0.09 and p = 0.15, respectively). CONCLUSIONS: Approximately 57.3% of the population 35 years and older in the INK area of Durban were affected by refractive errors, with myopia, hyperopia, and astigmatism being significantly associated with sex. This study suggests that there is a need for interventions to alleviate refractive error in the INK area as well as in other communities affected by the lack of access to affordable services.

Prevalence of vision impairment and refractive error in school children in Ba Ria - Vung Tau province, Vietnam.

BACKGROUND: To assess the prevalence of vision impairment and refractive error in school children 12-15 years of age in Ba Ria - Vung Tau province, Vietnam. DESIGN: Prospective, cross-sectional study. PARTICIPANTS: 2238 secondary school children. METHODS: Subjects were selected based on stratified multistage cluster sampling of 13 secondary schools from urban, rural and semi-urban areas. The examination included visual acuity measurements, ocular motility evaluation, cycloplegic autorefraction, and examination of the external eye, anterior segment, media and fundus. MAIN OUTCOME MEASURES: Visual acuity and principal cause of vision impairment. RESULTS: The prevalence of uncorrected and presenting visual acuity ≤6/12 in the better eye were 19.4% (95% confidence interval, 12.5-26.3) and 12.2% (95% confidence interval, 8.8-15.6), respectively. Refractive error was the cause of vision impairment in 92.7%, amblyopia in 2.2%, cataract in 0.7%, retinal disorders in 0.4%, other causes in 1.5% and unexplained causes in the remaining 2.6%. The prevalence of vision impairment due to myopia in either eye (-0.50 diopter or greater) was 20.4% (95% confidence interval, 12.8-28.0), hyperopia (≥2.00 D) was 0.4% (95% confidence interval, 0.0-0.7) and emmetropia with astigmatism (≥0.75 D) was 0.7% (95% confidence interval, 0.2-1.2). Vision impairment due to myopia was associated with higher school grade and increased time spent reading and working on a computer. CONCLUSIONS: Uncorrected refractive error, particularly myopia, among secondary school children in Vietnam is a major public health problem. School-based eye health initiative such as refractive error screening is warranted to reduce vision impairment.

Prevalence of presbyopia and spectacle coverage in an African population in Durban, South Africa.

PURPOSE: To assess the prevalence of near vision impairment caused by uncorrected presbyopia and to determine the spectacle coverage for presbyopia in Durban, KwaZulu Natal, South Africa. METHODS: A cross-sectional community-based survey was conducted to determine the prevalence of presbyopia in Durban. Eighteen clusters were randomly selected from the suburbs of Durban--Inanda, Ntuzuma, and KwaMashu. Adults over 35 years of age were enumerated through a door-to-door method using aged-based sampling. Respondents were interviewed and then underwent standardized clinical eye examinations. Spectacle coverage was determined. Applying multivariate logistic regressions, the strengths of association of presbyopia and spectacle coverage with the participants' demographic profile were determined. RESULTS: A total of 2764 participants were enumerated while 1939 (70.2%) were examined with a median age of 52 years (interquartile range 45, 60). The prevalence of presbyopia was 77.0% (95% confidence interval [CI] 74.3%-79.2%), significantly higher in those 50-64 years old (OR 10.2, 95% CI 5.3-19.6) and 65-79 years old (OR 10.7, 95% CI 3.2-35.6) and significantly lower in those who had secondary and higher education (p < 0.05). The spectacle coverage for presbyopia was 4.84% (95% CI 3.35%-6.33%), significantly higher in those who were 65-79 years old (OR 4.4, 95% CI 1.5-12.9) and 50-64 years old (OR 2.6, 95% CI 1.1-6.1). CONCLUSIONS: This study indicated that there is a high prevalence of presbyopia in the study area, with low spectacle coverage, and therefore suggests that uncorrected presbyopia is a major public health concern. The findings of this study may help in making recommendations for strategic planning for eye health intervention efforts.

Scaling up the delivery of refractive error services within a district health system: the KwaZulu-Natal, South Africa experience.

BACKGROUND: In South Africa, the health service is based on a Primary Health Care (PHC) philosophy with the District Health System (DHS) as the locus of delivery. However eye care services, particularly primary eye care, refractive error and low vision, have not been prioritised accordingly. Hence the aim of the Giving Sight to KwaZulu-Natal (GSKZN) project was to integrate the delivery of eye care services into the district health system, with emphasis on addressing the need for uncorrected refractive error and low vision services.The project was implemented in the KwaZulu-Natal province, South Africa, to scale up the delivery of refractive error services utilising a four pronged approach; including advocacy, human resource development, equipment provision and research. METHODS: This paper is a description of the project and a retrospective analysis of data received through the course of the project from July 2007 to June 2011. Data were collected from training registers, equipment schedules and service delivery reports from institutions. Reports from the data base were then analysed and achievements in training and trends in service delivery were determined. RESULTS: Over a four year period (July 2007 and July 2011) 1004 persons received training in rendering eye health services appropriate to their level of deployment within the DHS. During the course of the project, these 1004 persons examined 1,064,087 patients. Furthermore, the total number of clinics offering primary eye care, refractive error and low vision services increased from 96 (10%) to 748 (76%). With increased numbers of PHC Nurses trained in primary eye care, a subsequent decrease of 51.08 percent was also observed in the number of patients seeking services at higher levels of care, thus streamlining eye health service delivery. CONCLUSION: This project has shown that scaling up can occur in delivering eye health services within a health district, through a multi-faceted approach that encompasses focused training, advocacy, development of appropriate infrastructure and the development of referral criteria with clear guidelines for the management of patients.

Rapid assessment of refractive error in the eThekwini Municipality of KwaZulu-Natal, Durban, South Africa.

BACKGROUND: Population-based studies involving refractive error in South Africa are few because they are expensive to conduct and require a high level of expertise. Rapid assessment of refractive error (RARE) is a relatively less resource-intensive method designed to assess the magnitude of uncorrected refractive error (URE), spectacle coverage and barriers to access of services. This information is useful for designing and implementing programs as well as for policy development. PURPOSE: The purpose of this study was to determine the prevalence of uncorrected refractive error and spectacle coverage and to explore the barriers to uptake of refractive services in persons 15 to 35 years old in the eThekwini municipality, Durban, South Africa. METHODS: A cross-sectional epidemiological study was conducted using the RARE protocol. A total of 1,543 participants were enumerated and 1,516 were examined. Uncorrected refractive error was defined as presenting visual acuity less than 6/12 that could be corrected to 6/12 or better using a pinhole. Spectacle coverage was defined as the proportion of need that was already met with spectacle correction. RESULTS: The prevalence of age and sex adjusted URE was 1.5% (95 per cent CI: 0.7 -2.3). Odds for uncorrected refractive error in women were 0.5 (95 per cent CI: 0.3-0.9) lower compared to men. There was a statistically significant association between uncorrected refractive error and respondents 15 to 24 years old (p < 0.001). The spectacle coverage (6/12 cut-off) was 51.4 per cent (95 per cent CI: 28.1-74.7). The prevalence of spectacle use among participants was 3.8 per cent. CONCLUSIONS: The low prevalence of uncorrected refractive error found in this study agrees with previous studies that indicate that despite uncorrected refractive error being the most common cause of visual impairment and the second most common cause of blindness worldwide, its prevalence is relatively low in South Africans.

Population-based study of presbyopia in Nicaragua.

BACKGROUND: Uncorrected presbyopia can greatly impact a person's quality of life and employment prospects. Nicaragua is the poorest country in Latin America and there are no population-based reports of prevalence of presbyopia in Nicaragua. METHODS: A cross-sectional population-based household survey was conducted. The sample was selected through random cluster sampling. Adults 35 years and older were enlisted through a door-to-door method using aged-based sampling. All enumerated household members 35 years and older were asked to attend a free visual acuity screening. Autorefraction was done and then uncorrected distance vision and near visual acuity were measured for all subjects. All those who had distance or near vision that was 6/12 or worse underwent a clinical examination, which included refraction at distance and near. Free spectacles were provided. RESULTS: Of the 3,390 subjects surveyed, 37.1 per cent reported that they wore spectacles on a regular basis. A total of 1,871 (55.2 per cent) of those enumerated were examined. The prevalence of near visual impairment (6/12 [N 6] or worse) was 79.6 per cent for the 35 to 49-year-old group, 97.3 per cent for the 50 to 64-year-old group and 96.7 per cent for the 65 and over group. Of those reporting for the examination, 82.2 per cent did not have glasses. Of those examined, 10 per cent did not need spectacles, four per cent were given spectacles for distance only, 38 per cent spectacles for distance and near, 42 per cent spectacles for near only and seven per cent were referred for medical evaluation due to ocular pathology. During the refractions, 91.5 per cent were corrected to 6/12 or better at distance and 89.4 per cent were corrected to 6/12 or better at near. CONCLUSION: The majority of the participants who were examined did not have the spectacles that they needed. Over one-third of those participants who presented without spectacles had distance vision better than 6/12 and could be improved to good near vision with ready-made near-only spectacles.

Outcomes of Pediatric Cataract Surgery in the Copperbelt Province of Zambia.

PURPOSE: To study the outcomes of pediatric cataract surgeries in children operated on in the Copperbelt Province of Zambia and the barriers to accessing surgery. METHODS: All children who had congenital, developmental, and traumatic cataracts operated on by lens aspiration, primary posterior capsulotomy, and anterior vitrectomy with posterior chamber intraocular lens implantation from 2012 to 2013 and followed up beyond 6 months were studied. Each child underwent a comprehensive preoperative evaluation. An active, assisted follow-up was done and parents were asked about reasons for delay between presentation and surgery. RESULTS: One hundred two eyes of 70 children met the inclusion criteria of the study. Preoperatively, 76 of 77 (98.7%) eyes in the congenital and developmental cataract group had presenting visual acuity of worse than 6/60. This improved postoperatively, with 19 (29.7%) eyes having best corrected visual acuity (BCVA) of better than 6/18, 23 (35.9%) having BCVA of 6/24 to 6/60, and 22 (34.4%) having BCVA of worse than 6/60. Older age (P = .005), better preoperative vision (P = .045) at presentation, unilaterality (P = .012), and delay between presentation and surgery (P = .004) were predictors of a better postoperative outcome. On multivariate analysis, only age was significant (P = .025). Distance and cost of travel and surgery were the causes of delay in presentation. In the patients with traumatic cataracts, 17 of 25 (68%) had BCVA of better than 6/18, 6 (24%) had BCVA between 6/24 and 6/60, and 2 (8%) had BCVA of worse than 6/60 at the 6-month follow-up. The most common causes of injury were being struck by sticks and stones (10 children, 25%). CONCLUSIONS: Visual outcomes after pediatric cataract surgery in Zambia were comparable and satisfactory. Cost of treatment was a barrier, but delay did not adversely affect outcome. [J Pediatr Ophthalmol Strabismus. 2016;53(5):311-317.].

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.

Prevalence of refractive error, presbyopia and spectacle coverage in Kahama District, Tanzania: a rapid assessment of refractive error.

BACKGROUND: In Tanzania, the prevalence of refractive error and presbyopia have not been comprehensively assessed, limiting appropriate planning and implementation of delivery of vision care. This study sought to determine the prevalence of refractive error and presbyopia, spectacle coverage and the barriers to uptake of refractive services in people aged 15 years and older in the Kahama district of Tanzania. METHODS: A cross-sectional community-based survey was conducted using 54 randomly selected clusters. Respondents 15 years and older were interviewed and underwent standardised clinical eye examinations. Uncorrected refractive error (URE) was defined as presenting vision worse than 6/12 that could be corrected to better than 6/12 using a pinhole. Spectacle coverage was defined as the proportion of need that was met (those that improved from unaided vision with their own spectacle correction). RESULTS: A total of 3,230 subjects (99.75 per cent of 3,240 eligible) participated in the study with 57.2 per cent males and the median age of participants was 35 years (inter-quartile range, 24 to 49). The prevalence of visual impairment was 10.4 per cent (95% CI 9.4 to 11.4) and was lower in those who had completed their primary school education (odds ratio (OR) 0.54, 95% CI: 0.40 to 0.72) and highest in subjects 40 years and older (OR 3.17, 95% CI: 2.14 to 4.70) and farmers (OR 8.57 95% CI: 2.27 to 32.43). Refractive error prevalence was 7.5 per cent (95% CI: 6.65 to 8.54) and this was highest in participants over 40 years (OR 1.60, 95% CI: 1.14 to 2.25) and in students (OR 3.64, 95% CI: 1.35 to 9.86). Prevalence of presbyopia was 46.5 per cent (773/1,663, 95% CI: 44.34 to 48.75). Spectacle coverage for refractive error and presbyopia was 1.69% (95% CI: 0 to 3.29) and 0.42% (95% CI: 0 to 1.26), respectively. CONCLUSION: Uncorrected refractive error is a public health challenge in the Kahama district and sustainable service delivery and health promotion efforts are needed.

Prevalence of refractive error and spectacle coverage in Zoba Ma'ekel Eritrea: a rapid assessment of refractive error.

PURPOSE: To determine the prevalence of refractive error and spectacle coverage in Zoba Ma'ekel, Eritrea in order to assist in planning for refractive services and blindness prevention strategies. METHODS: A community-based cross-sectional study using multistage cluster sampling was conducted. A total of 3200 participants aged 15-50 years were enumerated and examined using the Rapid Assessment of Refractive Error (RARE) protocol. RESULTS: The response rate was 99.1%. The prevalence of refractive error was 6.4% (95% confidence interval [CI], 5.6-7.2%). Spectacle coverage for refractive error was 22.2% (95% CI 16.7-28.5%). It was higher among males than females (Fisher's exact test, p = 0.028), and highest in those who had completed secondary school (48.6%, 95% CI 31.9-65.6%) and those who resided in Asmara (Fisher's exact test, p < 0.002). The prevalence of presbyopia was 32.9% (95% CI 30.3-35.7%) with 94.9% correctable. Spectacle use for presbyopia was 9.9% (95% CI 7.2-13.4%), which was lowest in those with no formal schooling but highest in those who had completed secondary school (χ(2) test, p < 0.001) and those persons who resided in Asmara (Fisher's exact test, p < 0.001). Respondents expressed different barriers to uptake of services. A total of 128 subjects were aware of the problem but did not feel the need for consultation while 83 subjects stated they could not afford the cost of examination and spectacles. CONCLUSION: The study provides helpful findings to assist with the development of appropriate refractive service planning in Zoba Ma'ekel. Uncorrected refractive error is of public health importance and prompt measures are needed to address the problem.

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