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Purpose: To estimate the prevalence of and factors associated with diabetic retinopathy (DR) among people aged ≥50 years in Nakuru, Kenya. Methods: Probability-proportional-to-size sampling was used to select 100 clusters of 50 people aged ≥50 years during 2007-2008. Households within clusters were selected through compact segment sampling. Participants underwent dilated slit lamp biomicroscopy (SLB) by an ophthalmologist and digital retinal photography. Images were graded for DR at the Moorfields Eye Hospital Reading Centre, UK. Diagnosis of DR was based on retinal images where available, otherwise on SLB. Anthropometric measures, including random glucose, and lifestyle factors were measured. Results: We examined 4414 adults (response rate 88.1%), of whom 287 had diabetes. A total of 277 of these were screened for DR by SLB, and 195 also underwent retinal photography. The prevalence of any DR diagnosed by retinal images among diabetics was 35.9% (95% confidence interval, CI, 29.7-42.6%). The most common grade of DR was mild/moderate non-proliferative DR (NPDR; 22.1%, 95% CI 16.1-29.4%), while severe NPDR and proliferative DR were less frequent (13.9%, 95% CI 10.0-18.8%). SLB significantly underdiagnosed DR compared to retinal photography, particularly for milder grades. Of 87 individuals with DR, 23 had visual impairment (visual acuity <6/12). DR was associated with younger age, male sex, duration and control of diabetes, and treatment compliance. Coverage of photocoagulation in those needing immediate laser was low (25%). Conclusion: DR remains a threat to sight in people with diabetes in this elderly Kenyan population. Screening diabetics may enable those requiring treatment to be identified in time to preserve their sight. [ABSTRACT FROM AUTHOR]

Purpose: Cataract is the leading cause of blindness worldwide, and is particularly common in low- and middle-income countries. Our study aims to identify the predictors for and barriers to acceptance of cataract surgery in Kenya, Bangladesh and the Philippines. Methods: Cases were individuals aged ≥50 years and with best corrected VA of <6/24 in the better eye due to cataract who were identified through population-based surveys and community-based case detection. Cases were asked why they had not attended for surgery. They were offered free cataract surgery and followed-up at one year. Non-acceptors were interviewed to identify barriers to accepting surgery. Results: Of all participants, 58.6% attended for cataract surgery in Kenya, 53.9% Bangladesh and 47.1% the Philippines. Younger age was a predictor for attendance for surgery in all three countries. In Bangladesh and Kenya, male gender and psychosocial score were predictors. At baseline 'cost' and 'unaware of cataract' were most frequently reported barriers to uptake of surgery in the three settings. At follow-up, 'surgical services inaccessible' was one of the two most frequently reported barriers in Kenya and the Philippines while 'fear' was most frequently reported in Bangladesh and the Philippines. There were no consistent predictors of the most frequently reported barriers across the different settings. Conclusions: Future services need to focus on increasing uptake among older people and women. Cost is often reported as a barrier but this may conceal more complicated underlying barriers which need to be explored through in-depth qualitative research. [ABSTRACT FROM AUTHOR]

Purpose: To apply a previously described mathematical model, designed to estimate cataract incidence from age-specific prevalence, to Rapid Assess of Avoidable Blindness survey data from Sub-Saharan Africa in order to estimate the incidence of cataract and therefore surgical needs. Methods: All Rapid Assessment of Avoidable Blindness surveys from Sub-Saharan Africa were identified. A previously developed mathematical model, designed to estimate the incidence of operable cataract was applied to those (27/32) meeting the inclusion criteria. Results: Incidence varied significantly across the continent with the result that cataract surgery rate targets required to eliminate cataract vary too. When variation in age structure is also taken into account, the cataract surgery rate needed to eliminate cataract visual impairment at the level of 6/18 ranges from 1200-4500 surgeries per year per million population. Conclusions: This is important evidence of significant variation in the incidence of cataract within Sub-Saharan Africa. The variation may be related to genetic or cultural variations on the continent and has important implications for planning services. [ABSTRACT FROM AUTHOR]

Purpose: To determine the prevalence and causes of blindness, severe visual impairment and visual impairment as well as cataract surgical coverage in two northern provinces of Burundi for the purpose of planning eye services. Methods: The population-based Rapid Assessment of Avoidable Blindness survey methodology was used. Results: Of 3800 people enrolled, 3684 (97%) were examined. The sample prevalences of blindness, severe visual impairment, and visual impairment were 1.1% (95% confidence interval, CI 0.8-1.4), 0.6% (95% CI 0.4-0.9), and 1.7% (95% CI 1.3-2.1), respectively. The leading causes of blindness were cataract (55%) and posterior segment causes (37%). Severe visual impairment was mainly due to cataract (43%) and refractive error (39%), and visual impairment was mainly due to refractive error (67%) and cataract (18%). Cataract surgical coverage by person at the level of <6/60 was 15%. Conclusions: The low prevalence of vision loss in this area with no eye services and a low cataract surgical coverage rate is surprising and possibly due to the effects of the previous years of conflict in which those with decreased vision may have been most likely to perish. If this explanation is correct, then Burundi needs to plan to deal with a markedly increasing prevalence of cataract in future. [ABSTRACT FROM AUTHOR]

Purpose: Type 2 idiopathic macular telangiectasia (MacTel) is a progressive retinal disease associated with a slow deterioration of visual acuity, starting in the fifth to seventh decades of life. The etiology and pathogenesis of the disease are little known, and no effective therapy is available. We aimed to estimate the prevalence and describe the phenotype of type 2 MacTel in two African populations. Methods: From two population-based cross-sectional surveys conducted nationally in Nigeria and in the Nakuru district of Kenya, patients with fundus features of type 2 MacTel were selected. Diagnosis was based on color fundus images, grading performed according to the MacTel Study protocol and staged using the Gass and Blodi system. Disease phenotype and clinical characteristics of affected participants were assessed. Results: Of 8599 total participants, five showed a phenotype compatible with type 2 MacTel. Prevalence was estimated as 0.06% (95% confidence interval [CI] 0.02-0.21%) in Kenya, 0.06% (95% CI 0.01-0.17%) in Nigeria, and overall at 0.06% (95% CI 0.02-0.14%). Mean age was 62 years (SD 5 years), four of five affected participants were female, and none had a history of diabetes. Median corrected visual acuity was 6/12 in the better eye and 6/69 in the worse eye. Conclusions: The estimated prevalence and phenotype of type 2 MacTel in the African populations examined were similar to those in predominantly white populations. All data published so far are based on the analysis of color fundus images only and are thus likely to underestimate the true prevalence of this disease. [ABSTRACT FROM AUTHOR]

Purpose: To collect baseline data for planning of the National Blindness Prevention & Control Program and for monitoring future achievements. Methods: Sixty six clusters of 50 people were selected from a sampling frame that included all 2,593 villages in Eritrea (population 3.56 million). Within each selected village, 50 eligible people aged 50++ years were selected. All eligible participants underwent visual acuity (VA) measurement followed by examination by an ophthalmologist if the presenting VA (PVA) was less than 6/18. Results: Three thousand one hundred sixty three of the 3300 eligible persons were examined (coverage 95.9%). The adjusted prevalence of blindness (PVA < 3/60 in the better eye) in the survey population was 7.5% (95% confidence interval [CI]: 6.2--8.8%), bilateral severe visual impairment (PVA < 6/60 to ≥≥ 3/60 in the better eye) 3.0% (95% CI: 2.3--3.7%) and of bilateral moderate visual impairment (PVA < 6/18 to ≥≥ 6/60 in the better eye) 10.5% (95% CI: 9.1--11.9%). Of all bilateral blindness 55% was due to cataract. The adjusted cataract surgical coverage (percentage of people requiring cataract surgery that have had surgery) was 68% for blind people and 41% for blind eyes. Cataract surgery outcome was poor (PVA < 6/60) in 39% of all eyes operated in the past. Conclusions: The prevalence of blindness was high compared to recent surveys in Africa. Visual outcome after cataract surgery potentially could be improved by more detailed pre-operative examination, coaching of surgeons, and provision of adequate optical correction, including routine monitoring of visual outcome after cataract surgery. The development of intervention programs for refractive error and glaucoma should be considered. [ABSTRACT FROM AUTHOR]

Purpose: To assess the impact of cataract surgery on vision related quality of life (VRQoL) and generic health related quality of life (HRQoL) in Kenya, Bangladesh and the Philippines. Methods: A multi-center intervention study was conducted. At baseline 651 cases aged ≥50 years with visually impairing cataract (corrected visual acuity (VA) <6/24) and 561 age- gender-matched controls with normal vision (VA>6/18) were interviewed about VRQoL (using the World Health Organization/ Prevention of Blindness and Deafness 20-item Visual Functioning Questionnaire [WHO/PBD VF20]) and generic HRQoL (EuroQol). Cases were offered free/subsidized cataract surgery. Approximately 1 year later participants were re-interviewed. Results: Response rate at follow up was 84% for operated cases and 80% for controls. At baseline, cases had significantly poorer VRQoL scores, were more likely to report problems with the EuroQol 5D five descriptive (EQ−SD) domains (mobility, daily activities, self-care, pain, depression/anxiety) and had significantly poorer self-rated health compared to controls. At follow up VRQoL scores of operated cases improved significantly to approximately equal those of controls. Effect sizes were large (> 0.8) regardless of pre-operative VA. Poor outcome from surgery (VA < 6/60) was associated with smaller VRQoL gains. Among operated cases frequency of reported problems with all the EQ-5D reduced significantly compared to baseline in Kenya and the Philippines, and in mobility, daily activities and self-care in Bangladesh. Self-rated health scores increased significantly in each country. HRQoL of controls remained stable from baseline to follow up. Conclusion: This study among adults undergoing cataract surgery in 3 different low-income settings found evidence of improved VRQoL and generic HRQoL to approximately equal that of controls with normal vision. [ABSTRACT FROM AUTHOR]

Purpose: Cataract is the leading cause of blindness in the world, and is particularly common in low-income countries. Cataract is asserted to increase poverty through reduced productivity; however there is a lack of empirical data supporting this claim. The aim of this study was to examine the relationship between visual impairment from cataract with time-use in adults (aged ≥ 50 years) in Kenya, Bangladesh, and The Philippines. Methods: A population-based case-control study was conducted in three countries. Detailed time-use data were collected through interview from 139, 216 and 238 cases with visually impairing cataract and 124, 280 and 163 controls with normal vision in Kenya, Bangladesh and Philippines, respectively during 2005-2006. Results: Cases were substantially less likely than controls to participate in productive activities, including paid work and non-market activities (odds ratio [OR] across three countries is 0.2 95% confidence interval (CI): 0.1-0.3) and in leisure outside of the household (OR 0.7, 95% CI: 0.5, 0.9). Among cases, those with more severe visual impairment spent significantly less time on productive activities and leisure outside of the home, and more time on “no particular activity” (Kenya and Bangladesh) or leisure in the home (The Philippines). Cases were substantially more likely to require assistance in any activity than controls in Kenya (OR 9.8, 95% CI: 3.3, 29.8), Bangladesh (OR 8.6, 95% CI: 5.1-14.4) and the Philippines (OR 2.7, 95% CI: 1.4-5.1). Conclusions: Cataract visual impairment restricts engagement in productive and leisure activities in this population of older adults in three different low income settings. [ABSTRACT FROM AUTHOR]

An introduction to articles published within the issue is presented, including one on the prevalence, causes and risk factors of visual impairment, another on refractive error in children in Egypt as well as one on the uptake, barriers and outcomes of patients attending free cataract surgery.