Reducing inequity of cataract blindness and vision impairment is a global priority, but where is the evidence?

Throughout the world, people who are socially or economically disadvantaged disproportionately experience blindness and vision impairment caused by cataract. Reducing vision loss from cataract and its unequal distribution must be a priority if the WHO's aim of 'universal eye health' is to be realised. To help achieve this, decision-makers and service planners need evidence on which strategies improve access to cataract services among disadvantaged populations, and under what circumstances. Unfortunately, despite many strategies to improve cataract services being implemented in recent decades, evidence of what works, for who and in what circumstances is not readily available. This paper summarises the extent of the evidence on interventions to reduce inequity of vision loss from cataract and makes suggestions for how the evidence base can be strengthened

Coverage of hospital-based cataract surgery and barriers to the uptake of surgery among cataract blind persons in nigeria: the Nigeria National Blindness and Visual Impairment Survey.

PURPOSE: To determine cataract surgical coverage, and barriers to modern cataract surgery in Nigeria. METHODS: Multistage stratified cluster random sampling was used to identify a nationally representative sample of 15,027 persons aged 40+ years. All underwent visual acuity testing, frequency doubling technology visual field testing, autorefraction, and measurement of best corrected vision if <6/12 in one or both eyes. An ophthalmologist examined the anterior segment and fundus through an undilated pupil for all participants. Participants were examined by a second ophthalmologist using a slit lamp and dilated fundus examination using a 90 diopter condensing lens if vision was <6/12 in one or both eyes, there were optic disc changes suggestive of glaucoma, and 1 in 7 participants regardless of findings. All those who had undergone cataract surgery were asked where and when this had taken place. Individuals who were severely visually impaired or blind from unoperated cataract were asked to explain why they had not undergone surgery. RESULTS: A total of 13,591 participants were examined (response rate 89.9%). Prevalence of cataract surgery was 1.6% (95% confidence interval 1.4-1.8), significantly higher among those aged ≥70 years. Cataract surgical coverage (persons) in Nigeria was 38.3%. Coverage was 1.7 times higher among males than females. Coverage was only 9.1% among women in the South-South geopolitical zone. Over one third of those who were cataract blind said they could not afford surgery (36%). CONCLUSIONS: Cataract surgical coverage in Nigeria was among the lowest in the world. Urgent initiatives are necessary to improve surgical output and access to surgery

Couching in Nigeria: prevalence, risk factors and visual acuity outcomes.

PURPOSE: Couching is an ancient treatment for cataract which is still practiced in some of the poorer developing countries, particularly in sub-Saharan Africa. The purpose of this study is to describe risk factors for couching and visual acuity outcomes in a nationally representative sample of adults aged 40 years and above in Nigeria. METHODS: Probability in proportion size methods were used to identify a representative sample. Of the 15,375 adults enumerated, 13,582 were interviewed and examined. Examination included logMar acuities, slit lamp examination and dilated fundoscopy with digital fundus imaging. RESULTS: Almost half of the 583 eyes undergoing a procedure for cataract had been couched (249 eyes, 42.7%). Individuals living in rural areas (P = 0.033) and in the two underserved northern administrative zones (P = 0.33; P = 0.002) were more likely to have been couched. Visual outcomes were poor according to World Health Organization categories, with 55.8% of people and 73.1% of eyes having a presenting visual acuity of less than 3/60 and only 9.7% and 2.4% of people and eyes respectively having a good outcome (6/18 or better). None were wearing an aphakic correction, and with correction acuities improved but 42.6% of eyes were still blind (< 3/60). CONCLUSIONS: Couching is still widely practiced in Nigeria and visual outcomes are very poor. The population needs to be made aware of the risks associated with the procedure, and services for high quality, affordable cataract surgery need to be expanded, particularly in rural areas and in the north of the country

Outcome of paediatric cataract surgery in Northwest Ethiopia: a retrospective case series.

AIM: To assess visual acuity outcomes, and factors associated with the outcome, of paediatric cataract surgery at the Child Eye Health Tertiary Facility, Gondar, Northwest Ethiopia. METHODS: The medical records of children aged below 16 years who underwent cataract surgery between September 2010 and August 2014 were reviewed for preoperative, surgical and postoperative data. RESULTS: One hundred and seventy-six eyes of 142 children (mean age 7.9 years±4.2 SD, 66% male) who had cataract surgery were included. Twenty-five per cent (35/142) of children had bilateral cataract, 18 (13%) had unilateral non-traumatic cataracts and 89 (63%) had unilateral traumatic cataracts. An intraocular lens was implanted in 93% of eyes. Visual acuities at last follow-up: bilateral cases in the better eye: good (≥6/18 or fix and follow) in 21/34 eyes (62%), borderline (<6/18-6/60) in 4 eyes (12%) and poor (<6/60) in 9 eyes (26%). In unilateral non-traumatic cases: good in 6 eyes (33%), borderline in 3 eyes (17%) and poor in 9 eyes (50%). In unilateral traumatic cases: good in 36 eyes (40%), borderline in 20 eyes (23%) and poor in 33 eyes (37%). In bilateral cataract, worse outcomes were associated with preoperative nystagmus/strabismus. In traumatic cases, worse outcomes were associated with the preoperative trauma-related complications. CONCLUSIONS: Visual acuity improved significantly after surgery, with better outcomes in bilateral cases. Early detection and surgery by a trained surgeon with good follow-up and postoperative rehabilitation can lead to better visual outcomes

Gender Inequalities in Surgery for Bilateral Cataract among Children in Low-Income Countries: A Systematic Review.

PURPOSE: Cataract is a common cause of avoidable blindness in children globally. Gender differences in service access among children are reported for several conditions, but not for surgery for bilateral cataract. In this review we compared the proportion of children undergoing surgery for bilateral, nontraumatic cataract who were girls, using data from high-income, gender-neutral countries as the reference. DESIGN: Systematic review. METHODS: A systematic review of MEDLINE was undertaken in November 2014. Studies published only from 2000 onward were included because techniques and services have improved over time. A wide range of study designs was included such as: population-based data, registers, studies of surgical techniques, clinical trials, and so forth. All articles with 20 or fewer cases were excluded or were of long-term follow-up only, because this may reflect gender differences during follow-up. A meta-analysis was not planned. RESULTS: Thirty-eight studies (6854 children) were included from 1342 titles, 10 from high-income countries. Many did not present data disaggregated by gender. Overall, 36.5% of children were girls. In gender-neutral countries, 47.5% of children (777/1636) were girls, being similar in the Middle East, North Africa, and Central Asia (48.6%; 87/179) and in Latin America and the Caribbean (43.7%; 188/430). Proportions were significantly lower in sub-Saharan Africa (41.1%; 225/547), East Asia and the Pacific (36.0%; 237/658), and South Asia (29.1%; 991/3404). CONCLUSIONS: Access to surgery by girls with bilateral cataract is lower in some regions than by boys. Barriers to access specific to girls need to be identified, particularly in Asia, to assess interventions to improve uptake

Why do people not attend for treatment for trachomatous trichiasis in Ethiopia? A study of barriers to surgery.

BACKGROUND: Trachomatous trichiasis (TT) surgery is provided free or subsidised in most trachoma endemic settings. However, only 18-66% of TT patients attend for surgery. This study analyses barriers to attendance among TT patients in Ethiopia, the country with the highest prevalence of TT in the world. METHODOLOGY/PRINCIPAL FINDINGS: Participants with previously un-operated TT were recruited at 17 surgical outreach campaigns in Amhara Region, Ethiopia. An interview was conducted to ascertain why they had not attended for surgery previously. A trachoma eye examination was performed by an ophthalmologist. 2591 consecutive individuals were interviewed. The most frequently cited barriers to previous attendance for surgery were lack of time (45.3%), financial constraints (42.9%) and lack of an escort (35.5% in females, 19.6% in males). Women were more likely to report a fear of surgery (7.7% vs 3.2%, p<0.001) or be unaware of how to access services (4.5% vs 1.0% p<0.001); men were more frequently asymptomatic (19.6% vs 10.1%, p<0.001). Women were also less likely to have been previously offered TT surgery than men (OR = 0.70, 95%CI 0.53-0.94). CONCLUSIONS/SIGNIFICANCE: The major barriers to accessing surgery from the patients' perspective are the direct and indirect costs of surgery. These can to a large extent be reduced or overcome through the provision of free or low cost surgery at the community level. TRIAL REGISTRATION: ClinicalTrials.gov NCT00522860 and NCT00522912

Prevalence and causes of functional low vision in school-age children: results from standardized population surveys in Asia, Africa, and Latin America.

PURPOSE: Data on the prevalence and causes of functional low vision (FLV) in adults and children are lacking but are important for planning low-vision services. This study was conducted to determine the prevalence and causes of FLV among children recruited in eight population-based prevalence surveys of visual impairment and refractive error from six countries (India [2 locations]; China [2 locations]; Malaysia, Chile, Nepal, and South Africa). METHODS: Using the same protocol, 4082 to 6527 children aged 5 (or 7) to 15 years were examined at each site. Uncorrected and presenting visual acuities were successfully measured with retroilluminated logMAR tumbling-E charts in 3997 to 5949 children; cycloplegic autorefraction was performed and best corrected acuities assessed. All children were examined by an ophthalmologist and a cause of visual loss assigned to eyes with uncorrected acuity < or =6/12. The prevalence of FLV was determined overall and by site; associations with gender, age, parental education and urban/rural location were assessed with logistic regression. RESULTS: The prevalence of FLV ranged from 0.65 to 2.75 in 1000 children, with wide confidence intervals. The overall prevalence was 1.52 in 1000 children (95% CI 1.16-1.95). FLV was significantly associated with age (odds ratio [OR] 1.13 for each year, P = 0.01), and parental education was protective (OR 0.75 for each of five levels of education, P = 0.017). Retinal lesions and amblyopia were the commonest causes. CONCLUSIONS: More studies are needed to determine the prevalence and causes of FLV in children so that services can be planned that promote independence, improve quality of life, and increase access to education

Inequality in cataract blindness and services: moving beyond unidimensional analyses of social position.

OBJECTIVE: Inequalities in cataract blindness are well known, but data are rarely disaggregated to explore the combined effects of a range of axes describing social disadvantage. We examined inequalities in cataract blindness and services at the intersection of three social axes. METHODS: Three dichotomous social variables (sex (male/female); place of residence (urban/rural); literacy (literate/illiterate)) from cross-sectional national blindness surveys in Pakistan (2001-2004; n=16 507) and Nigeria (2005-2007; n=13 591) were used to construct eight subgroups, with disadvantaged subgroups selected a priori (ie, women, rural dwellers, illiterate). In each data set, the social distribution of cataract blindness, cataract surgical coverage (CSC) and effective cataract surgical coverage (eCSC) were examined. Inequalities were assessed comparing the best-off and worst-off subgroups using rate differences and rate ratios (RRs). Logistic regression was used to assess cumulative effects of multiple disadvantage. RESULTS: Disadvantaged subgroups experienced higher prevalence of cataract blindness, lower CSC and lower eCSC in both countries. A social gradient was present for CSC and eCSC, with coverage increasing as social position improved. Relative inequality in eCSC was approximately twice as high as CSC (Pakistan: eCSC RR 2.7 vs CSC RR 1.3; Nigeria: eCSC RR 8.7 vs CSC RR 4.1). Cumulative disadvantage was observed for all outcomes, deteriorating further with each additional axis along which disadvantage was experienced. CONCLUSIONS: Each outcome tended to be worse with the addition of each layer of social disadvantage. Illiterate, rural women fared worst in both settings. Moving beyond unidimensional analyses of social position identified subgroups in most need; this permits a more nuanced response to addressing the inequitable distribution of cataract blindness