Quality of life of the most severely vision-impaired

Background: To explore the interaction between vision impairment, perceived quality of life loss and willingness to trade remaining life for vision gain. Design: Community‐based cross‐sectional study Participants: Legally blind or severely vision‐impaired people selected randomly from the Association for the Blind of Western Australia register. Methods: Individuals were examined by consultant ophthalmologists and completed the Impact of Vision Impairment profile quality of life assessment and a Time Trade‐Off evaluation. Vision‐related utility values were calculated. The results were analysed using univariate and multivariate regression methods. Main Outcome Measures: IVI Rasch Logits and TTO utility values (TTO UV). Results: 156 people volunteered to contribute to the study. The median age was 80 (19–97) years, and 56% were female. Being legally blind (logMAR > 1) (95% CI 1.1 to 5.2, P = 0.003), clinically depressed (95% CI ?11.2 to ?1.8, P = 0.007) or more than 40 years of age (95% CI 0.9 to 8.1, P = 0.015) significantly lowered overall impact of vision impairment scores. The emotional domain of impact of vision impairment was associated with willingness to trade part of remaining life. A 5‐Logit increase in impact of vision impairment emotional score resulted in a 21% (95% CI 10 to 31) decrease in the odds of being likely to trade life for sight. The Australian definition of blindness compared with World Health Organisation or USA best separates those with perceived loss and appears useful in identifying vision loss‐related morbidity. Conclusions: These results suggest that emotional health and lack of depression are important determinants for quality and value of life.     

Factors associated with lifetime risk of open‐angle glaucoma blindness

Purpose: To investigate factors associated with bilateral glaucoma blindness, particularly factors available at the time of diagnosis. Methods: Retrospective chart review of all patients with primary open‐angle glaucoma (POAG) or pseudoexfoliative glaucoma (PEXG) followed at the Department of Ophthalmology or Low Vision Center of Skåne University Hospital, Malmö, Sweden, who died between January 2006 and June 2010. Disease stage at diagnosis was defined by a simplified version of Mills’ glaucoma staging system using perimetric mean deviation (MD) to define six stages of severity. Blindness was defined according to WHO criteria. We used logistic regression analysis to examine the association between risk factors and glaucoma blindness. Results: Four hundred and 23 patients were included; 60% POAG and 40% PEXG. Sixty‐four patients (15%) became blind from glaucoma. Blind patients had significantly longer mean duration with diagnosed disease than patients who did not go blind (14.8 years ± 5.8 versus 10.6 years ± 6.5, p < 0.001). The risk of blindness increased with higher intraocular pressure (IOP) (OR 1.08, 95% CI 1.03–1.13) and with each stage of more advanced field loss at time of diagnosis (OR 1.80 95% CI 1.34–2.41). Older age at death was also associated with an increased risk of blindness (OR 1.09 95% CI 1.03–1.14), while age at diagnosis was unimportant. PEXG was not an independent risk factor for blindness. Conclusions: Higher IOP and worse visual field status at baseline were important risk factors, as was older age at death.     

泉州市盲校学生视力损伤病因

目的：探讨泉州市盲校学生视力损伤的病因及残余视力的情况。方法：横断面研究。在2016 年期间对泉州盲校126 名低视力和盲学生进行病史采集,应用眼科常规检查方法对其行全面的眼科检查,并对学生的主要病因进行诊断和分析。结果：60 名盲学生的病因中：早产儿视网膜病变居第1 位,占23.3%（14 例）,角膜变性和视神经萎缩均列第2 位,各占13.3%（8 例）,第4 位为先天性青光眼占11.7%（7例）。66名低视力学生的病因中,先天性白内障居首位,占27.3%（18例）,眼球震颤为第2位,占13.7%（9 例）,视神经萎缩为第3 位,占10.6%（7 例）,角膜变性为第4 位,占9.1%（6 例）。结论：泉州市盲校的126 名学生中,先天性或遗传性疾病是导致视力损伤的主要原因,早产儿视网膜病变是致盲的首要病因,而先天性白内障是导致低视力的主要原因。     

Use of Cataract Services in Eastern Africa—A Study from Tanzania

Purpose: To establish the proportion of patients who are blind or have low vision prior to undergoing cataract surgery at tertiary referral centers in Tanzania. To assess which patient groups presenting for cataract surgery are more likely to be blind or visually impaired. Methods: Using pre-existing computerized audit systems we gathered data on pre-operative visual status, age, gender and presentation mode (walk-in or outreach) for 3765 patients undergoing 4258 cataract operations at 2 hospitals in Tanzania. Visual status was defined based on vision in the better eye. Results: 32% of operations were performed on blind patients, 37% on patients with low vision and 31% on normally sighted patients. Predictors of blindness at presentation were: female sex (OR 1.15; 95% CI 1.00–1.32); referral from a rural outreach program (OR 1.75; 95% CI 1.51–2.02) and older age (OR 1.02; 95% CI 1.01–1.02). Conclusions: It is not only the blind who present to cataract services in Tanzania. The demand for surgery amongst patients who or are normally sighted represents a positive move towards prevention, and not only cure of cataract blindness in Tanzania. However, it also highlights the need to target those left blind from cataract in order to deliver services to those most in need. Cataract programs targeting patients in rural areas and older patients are likely to increase the number of blind patients benefiting from cataract services.     

Prevalence and causes of blindness & low vision; before and five years after 'VISION 2020' initiatives in Oman: a review

BACKGROUND: A prevalence survey of blindness and low vision was conducted in Oman in 2005. Here, we present the prevalence and determinants of blindness and low vision among the population >or= 40 years of age. The results are then compared with those of the survey in 1997 and the changes following the 'VISION 2020' initiatives are assessed. METHODS: The survey covered 24 randomly selected clusters (75 houses in each). Teams assessed the distance vision of subjects while wearing glasses. The ophthalmologists examined the anterior segment and fundus to determine the causes of disability. The visual field was tested in those suspected of glaucoma. The prevalence rates of blindness (< 3/60 on presentation), legal blindness (< 6/60) and low vision (< 6/18) were calculated. The data from the 1997 survey was then analyzed to obtain similar rates in the population >or= 40 years of age. RESULTS: The prevalence of blindness was 8.25% (95% CI 7.14-9.36) in the >or= 40 year-old population in 2005. The rate would be 6.95% (95% CI 5.92-7.98) if blindness were defined as vision with best possible correction. The prevalence of legal blindness and low vision were 12% and 45.12%, respectively. In the 1997 survey, the prevalence of blindness in same age group was 7.23% (95% CI 5.91-8.55). Between the two surveys, the prevalence of blindness due to corneal pathology declined from 1.9% to 1.1% but that of blindness due to unoperated cataract increased from 1.8% to 2.3%. CONCLUSIONS: The rate of disability has declined but the number of blind people has increased in Oman. The causes of blindness have changed from communicable/avoidable eye diseases to non-curable/chronic eye diseases, and the number with visual disabilities has increased. An increasing number of operations for cataract and improvements in the care for glaucoma and diabetic retinopathy are recommended.     

Ocular trauma in an urban population in southern India: the Andhra Pradesh Eye Disease Study

Purpose : To assess the cumulative prevalence of ocular trauma and presence of vision loss due to ocular trauma in an urban population in southern India. Methods : As part of the population‐based Andhra Pradesh Eye Disease Study, 2522 people of all ages from 24 clusters representative of the population of Hyderabad city in southern India, underwent a detailed interview and standardized dilated ocular evaluation. An eye was considered to be blind due to trauma if best corrected distance visual acuity was worse than 6/60 due to trauma. Results : One hundred and thirteen subjects gave a history of ocular trauma and another two had evidence of ocular trauma by examination, a combined age–sex‐adjusted rate of 3.97% (95% CI 2.52–5.42%). Blindness in one eye due to trauma was present in 17 subjects, and in both eyes in one subject, a combined age–sex‐adjusted prevalence of 0.60% (95% CI 0.23–1.04%). Visual acuity in all the blind eyes except one was worse than 3/60. With multiple logistic regression, the odds of blindness in at least one eye due to trauma were highest for current age range of 30–39 years (odds ratio 6.33, 95% CI 1.69–23.77 compared with a current age of less than 30 years), were significantly higher for lower socioeconomic status (3.74, 95% CI 1.18–11.84), and were higher for males (2.48, 95% CI 0.91–6.82) though this did not reach statistical significance. Trauma resulting in blindness had occurred by the age of 15 years in 55% of subjects, and before the age of 40 years in 92.1% of subjects; this had occurred most commonly while playing (53.6% of the cases). With multiple logistic regression, the odds ratios for any ocular trauma were significantly higher for males (2.10, 95% CI 1.40–3.15), and for labourers than for other occupations (2.50, 95% CI 1.62–3.86). Conclusions : Ocular trauma affects one in 25 people in this urban population in India, and one in 167 people in this population are estimated to be blind in at least one eye due to trauma. The majority of the trauma resulting in blindness occurs during childhood and young adulthood, and slightly more than half occurs while playing. Targeting mothers and children of lower socioeconomic strata in eye health awareness strategies to reduce blindness due to trauma needs to be considered in urban India. Key words : blindness, India, population‐based, trauma, urban.     

Trends in registered blindness and its causes over 19 years in Western Australia

PURPOSE: To estimate the population-based incidence rates of blindness registration and their trends over time in Western Australia. METHODS: A retrospective review was performed on all cases of bilateral blindness registered with the Association for the Blind of Western Australia between 1984 and 2002. The causes and mean age at blindness registration were ascertained and incidence rates of blindness due to various causes were calculated. RESULTS: A total of 3852 blind certificates were examined. From 1984 to 1994, the annual incidence of registered bilateral blindness decreased significantly at an average rate of 9.4% per year (p < 0.0001), but then rose at a mean rate of 4.1% per year (p < 0.0001). ARMD blindness similarly fell by 8.9% per year (p < 0.0001), but then rose after 1994 by 4.5% per year (p < 0.0001). The incidence due to glaucoma decreased at an average rate of 10.3% per year (p < 0.0001) until 1994 and then rose at 7.4% per year at borderline significance (p = 0.025). CONCLUSIONS: There has been a nonlinear decrease in the incidence of registered blindness, in particular glaucoma-related blindness, in Western Australia. Rates of total registered blindness and that due to ARMD fell from 1984 to 1994, but have risen since.     

Cause-specific prevalence of bilateral visual impairment in Victoria, Australia: the Visual Impairment Project

PURPOSE: To study the cause-specific prevalence of eye diseases causing bilateral visual impairment in Australian adults. DESIGN: Two-site, population-based cross-sectional study. PARTICIPANTS: Participants were aged 40 years and older and resident in their homes at the time of recruitment for the study. The study was conducted during 1992 through 1996. METHODS: The study uses a cluster stratified random sample of 4744 participants from two cohorts, urban, and rural Victoria. Participants completed a standardized interview and eye examination, including presenting and best-corrected visual acuity, visual fields, and dilated ocular examination. The major cause of vision loss was identified for all participants found to be visually impaired. Population-based prevalence estimates are weighted to reflect the age and gender distribution of the two cohorts in Victoria. MAIN OUTCOME MEASURES: Visual impairment was defined by four levels of severity on the basis of best-corrected visual acuity or visual field: <6/18 > or =6/60 and/or <20 degrees > or =10 degrees radius field, moderate vision impairment; severe vision impairment, <6/60 > or =3/60 and/or <10 degrees > or =5 degrees radius field; and profound vision impairment <3/60 and/or <5 degrees radius field. In addition, less-than-legal driving vision, <6/12 > or =6/18, and/or homonymous hemianopia were defined as mild vision impairment. In Australia, legal blindness includes severe and profound vision impairment. RESULTS: The population-weighted prevalence of diseases causing less-than-legal driving or worse impairment in the better eye was 42.48/1000 (95% confidence interval [CI], 30.11, 54.86). Uncorrected refractive error was the most frequent cause of bilateral vision impairment, 24.68/1000 (95% CI, 16.12, 33.25), followed by age-related macular degeneration (AMD), 3.86/1000 (95% CI, 2.17, 5.55); other retinal diseases, 2.91/1000 (95% CI, 0.74, 5.08); other disorders, 2.80/1000 (95% CI, 1.17, 4.43); cataract, 2.57/1000 (95% CI, 1.38, 3.76); glaucoma, 2.32/1000 (95% CI, 0.72, 3.92); neuro-ophthalmic disorders, 1.80/1000 (95% CI, 0, 4.11); and diabetic retinopathy, 1.53/1000 (95% CI, 0.71, 2.36). The prevalence of legal blindness was 5.30/1000 (95% CI, 3.24, 7.36). Although not significantly different, the causes of legal blindness were uncorrected refractive errors, AMD, glaucoma, other retinal conditions, and other diseases. CONCLUSIONS: Significant reduction of visual impairment may be attained with the application of current knowledge in refractive errors, diabetes mellitus, cataract, and glaucoma. Although easily preventable, uncorrected refractive error remains a major cause of vision impairment.     

Visual impairment and blindness in rural central India: the Central India Eye and Medical Study

Purpose: The aim of the study was to investigate prevalence of visual impairment in rural central India. Methods: The population‐based Central India Eye and Medical Study included 4711 subjects with an age of 30+ years. Presenting visual acuity (PRVA) and best‐corrected visual acuity (BCVA) were recorded. Visual impairment and blindness were defined using the World Health Organization (WHO) standard and United States (US) standard. Results: On the basis of PRVA and using WHO and US standards, 1049 [22%; 95% confidence interval (CI): 21.1, 23.5] subjects and 1290 (27%; 95% CI: 26.1, 28.7) subjects, respectively, were visually impaired, and 35 (0.7%; 95% CI: 0.5, 1.0) subjects and 116 (2.5%; 95% CI: 2.0, 2.9) subjects, respectively, were blind. The corresponding age‐standardized prevalence figures were 17%, 21%, 0.5% and 2%, respectively. Using best‐correcting glasses could eliminate PRVA‐visual impairment/blindness in 729 subjects (67% of all subjects with visual impairment/blindness). On the basis of BCVA and using WHO and US standards, 333 (7%; 95% CI: 6.3, 7.8) subjects and 473 (10%; 95% CI: 9.2, 10.9) subjects, respectively, had visual impairment, and 22 (0.5%; 95% CI: 0.3, 0.7) and 31 (0.7%; 95% CI: 0.4, 0.9) subjects, respectively, were blind. Corresponding age‐standardized prevalence figures were 5%, 8%, 0.4% and 0.5%, respectively. Causes for BCVA‐visual impairment/blindness were cataract (75%), postoperative posterior capsular opacification (4%), surgical complications (2%), corneal opacifications (2%), age‐related macular degeneration (2%), other macular diseases (1%), and glaucoma (1%). Conclusions: Age‐standardized prevalence of PRVA‐visual impairment/blindness (WHO definition) in the adult population of rural central India was 17%. Most frequent cause was undercorrected refractive error. Supply of correct glasses is the most efficient way to improve vision in the rural central India.     

Five‐year incidence of visual impairment and blindness in older Icelanders: the Reykjavik Eye Study

Purpose: This study examined age, sex and cause‐specific 5‐year incidence of visual impairment and blindness in a middle‐aged and elderly Icelandic population. Methods: The study cohort consisted of a population‐based, random sample of citizens aged ≥ 50 years. Of 1379 eligible subjects, 1045 underwent a baseline examination in 1996; 846 of the 958 survivors (88.2%) underwent a 5‐year follow‐up examination in 2001. All participants underwent an extensive ophthalmological examination including best corrected visual acuity (BCVA) using a Snellen chart. We used World Health Organization (WHO) criteria, which define visual impairment as BCVA in the better eye of < 6/18 and ≥ 3/60 and blindness as BCVA in the better eye of < 3/60. We also used US criteria, which consider BCVA of < 6/12 and > 6/60 in the better eye to represent visual impairment and BCVA of ≤ 6/60 in the better eye to represent blindness. The causes of incident visual loss in either eye were determined. Deterioration or improvement in vision were defined as a loss or gain of ≥ 2 Snellen lines. Results: According to WHO criteria, 5‐year incidence of bilateral visual impairment and blindness were 1.07% (95% confidence interval [CI] 0.37–1.76) and 0.35% (95% CI 0.00–0.76), respectively. Using US criteria, equivalent incidence of bilateral visual impairment and blindness were 3.49% (95% CI 2.24–4.74) and 0.95% (95% CI 0.29–1.60), respectively. Age‐related macular degeneration and cataract were the major causes of incident visual impairment and blindness. Conclusions: Incidences of visual impairment and blindness increased significantly with age. Age‐related macular degeneration, present in 75% of affected persons, was the most common cause of 5‐year incident legal blindness in this middle‐aged and elderly Icelandic population.     

Prevalence of blindness and low vision: a study in the rural Heilongjiang Province of China

Background: The prevalence of blind individuals in the north of China is unknown. The study aimed to investigate the prevalence and causes of blindness and low vision in rural areas in Heilongjiang province of China in 2008–2009. Design: Cross‐sectional study. Participants or Samples: A cluster random sampling method was used to recruit participants of all ages in rural areas of Heilongjiang. Methods: Trained professionals performed interviews and clinical examinations to measure visual acuity. The relationships between blindness or low vision and age, gender and education level were analysed. Main Outcome Measures: The main outcome measure was prevalence rates of bilateral blindness and bilateral low vision. Results: Of the 11 787 subjects, 10 384 (88.1%) were surveyed. The overall age‐adjusted prevalence rates were 0.7% (95% confidence interval: 0.5–0.8%) for bilateral blindness and 1.7% (95% confidence interval: 1.4–1.9%) for bilateral low vision. The prevalence rates of blindness and low vision were higher in the elderly and uneducated population (P < 0.05). The main causes for blindness and low vision were cataracts (44.1 and 46.0%, respectively) and refractive errors (17.7 and 42.5%, respectively). Conclusion: Blindness and low vision are highly prevalent among people with cataracts and refractive errors. Eye care planning must focus on treating the avoidable and curable forms of blindness.     

Unrecognized and unregistered blindness in people 70 or older in Jing’an district, Shanghai, China

AIM: To evaluate the efficacy of a registration system for the blind people and to monitor the blindness due to uncorrected refractive error and cataract in Jing’an district, Shanghai, China.#$NLMETHODS: Five hundred and ten blind people, based on visual acuity screening in a population aged 70 or older were enrolled into the study. Four hundred and forty subjects were interviewed. The following data were collected on each patient:demographic data, number of hospital visits for eye related problems, distance visual acuity, visual fields, ophthalmic diagnoses, education and registration status. If the eligible subject was not registered as blind, the reason for non-registration was recorded.#$NLRESULTS: Ten point nine one percent blindness was due to cataract, 27.5% due to uncorrected refractive error, and only 61.59% met the eligible blindness criteria (uncorrected refractive error and cataract are not considered as eligible blindness). The first four leading causes of eligible blindness were age related macular degeneration (25.09%), myopic macular degeneration (21.40%), glaucoma (18.82%) and corneal disease (8.12%). Only 68.27% eligible blind people were registered. The patients with macular degeneration and glaucoma tended not to register. Blind people with an above primary school education were 2.59 times more likely to be registered than those who were illiterate or had only a primary school education (OR=2.59, 95%CI:1.49-4.48, P<0.01). Patients who had 4 or more visits to the hospital requesting eye care services in a year were 2.2 times more likely to be registered than those with less than 4 visits to the hospital (OR=2.54, 95%CI:1.47-4.38, P<0.001). The first two leading reasons of misregistration were unknowing the registration system (48%) and unwilling to register (21%). #$NLCONCLUSION: Under-registration of the eligible blind people exists in the registry system. Education and the number of hospital visits for eye care services were factors associated with registration levels. Uncorrected refractive error and cataract are important causes of blindness.     

Primary open-angle glaucoma presentation at a tertiary unit in Africa: intraocular pressure levels and visual status

AIM: To investigate the presentation of POAG at a tertiary referral hospital in East Africa, including intraocular pressures, visual status and management decisions. METHODS: Retrospective review of first-time presenters with POAG over a 6-month period. RESULTS: Of the 298 patients identified, mean age 57 years (n = 296, range = 14-88, SD = 14), 213 (72%) male, 122 (41%) had normal vision (using WHO better eye acuity criteria: visual impairment < 6/18, blind < 3/60) at presentation, 87 (30%) had visual impairment and 86 (29%) were blind. The mean presenting IOP was 32 mmHg (SD = 11) and 70% of the patients had a cup:disc ratio of 0.8 or worse in the better eye. Longer disease duration (OR = 1.20, 95% CI 1.04-1.39) and higher mean IOP (OR = 1.06, 95% CI 1.02-1.10) were associated with visual impairment or blindness. Intraocular pressure showed a negative linear correlation with presenting logMAR acuity (R(2) = 0.115, SE = 1.30, p < 0.0005). The mean IOP in eyes that had undergone trabeculectomy (19 mmHg, SD = 8, n = 17) was significantly (p < 0.0005) lower than that in eyes that had not (34 mmHg, SD = 12, n = 274). The referral rate for trabeculectomy was 158/275 (57%). Male sex (OR = 2.17, 95% CI 1.0-4.72), higher mean IOP (OR = 1.09, 95% CI 1.05-1.14) and not being blind (OR = 26.47, 95% CI 9.90-70.78) were associated with surgical referral. Of the 158 patients, 76 (48%) accepted surgery. CONCLUSIONS: A high proportion of patients presenting to our unit with POAG are visually impaired or blind and the higher their presenting IOP the poorer their visual acuity. Previous trabeculectomy was associated with lower IOPs and protection from visual impairment and blindness. Further training of clinic staff towards early surgical referral and investigation of gender barriers is required.     

Blindness and Low Vision in Cape Verde Islands: Results of a National Eye Survey

Aims: Prior to establishing a national prevention of blindness program a population based survey was conducted in Cape Verde Islands in1998. The objectives of the survey were to estimate the overall and age-specific prevalence of blindness and low vision, to identify the main disorders causing blindness and low vision, and to estimate the population need for basic eye care services. Methods: A two-level cluster random sampling procedure was used, selecting 30 clusters from the nine inhabited islands and 3,803 persons of all ages were included in the sample. Results: 3,374 persons were examined (coverage 88.7%). The prevalence of bilateral blindness (visual acuity in the better eye less than 3/60) was 0.8% (95% confidence interval [CI] 0.5–1.1), of bilateral low vision (6/18 to 3/60 in the better eye) 1.7% (95% CI: 1.3–2.2) and of monocular blindness 1.5% (95% CI: 1.2–2.0). The major causes of blindness were age related cataract and glaucoma (57.7% and 15.4%, respectively, of blind people recruited). The major causes of bilateral low vision were cataract, refractive errors, and macular disorders (46.2%, 26.8%, and 8.9%, respectively, of persons with low vision). Nontrachomatous corneal opacities accounted for 7.7% of bilateral and for 11.5% of monocular blindness. Vascular retinopathy was responsible for 7.7% of bilateral and for 9.6% of monocular blindness. Trachoma is not a public health problem as only 2.3% of children less than 10 years of age were suffering from active trachoma. Palpebral or limbal vernal conjunctivitis were encountered in 4.5% of persons under 25. Conclusion: More than half of the visual impairments are treatable by provision of cataract surgery and cataract has been indicated as a priority target in the recently designed National Blindness Program of the Cape Verde Republic. Pathologic conditions such as diabetes are emerging as serious burden for ageing populations and account for most of the retinal vascular disease.     

Diabetic retinopathy and the major causes of vision loss in Aboriginals from remote Western Australia

Purpose: To report on diabetic retinopathy (DR) and the major causes of vision loss and blindness in Aboriginals in the Eastern Goldfields region of Western Australia between 1995 and 2007. Methods: Aboriginals (>16 years old) diagnosed with diabetes or eye problems from 11 communities in the Eastern Goldfields region of Western Australia were examined annually from 1995 to 2007. Data collected from prospective clinical examination included; visual acuity (VA), causes of vision loss, and whether DR was present. Severity of DR was graded according to the Early Treatment of Diabetic Retinopathy Study modified Airlie House grading system. Results: A total of 920 Aboriginals underwent 1331 examinations over the study period. There were 246 eyes with vision loss (best‐corrected VA < 6/12) in 159 Aboriginals, of whom five were bilaterally blind. The four major known causes of vision loss were cataract (n = 53, 30.1%), DR (n = 44, 25.0%), uncorrected refractive error (n = 31, 17.6%) and trauma (n = 19, 10.8%). Aboriginals who had diabetes were far more likely to have vision loss (odds ratio = 8.5, 95% confidence interval 5.7–12.6, P < 0.0001). Of the 329 Aboriginals with diabetes, 82 (24.9%) had DR, and 32 (9.7%) had vision‐threatening retinopathy. Of those with diabetes, 94 (42.5%) returned for follow‐up examination on an average of 3.2 visits with a median time between visits of 2 years. Conclusion: The four major causes of vision loss in Aboriginals from the Eastern Goldfields are largely preventable and/or readily treated. DR and other diabetes‐related eye conditions are a major cause of vision loss in Aboriginals, representing a significant health challenge for health services and clinicians into the future.     

A population-based eye survey of older adults in a rural district of Rajasthan: I. Central vision impairment, blindness, and cataract surgery

PURPOSE: To assess the prevalence of central vision blindness and cataract surgery in older adults in rural northwest India. DESIGN: Population-based, cross-sectional study. PARTICIPANTS: A total of 4284 examined persons 50 years of age or older. METHODS: A random selection of village-based clusters was used to identify a population sample in the predominantly rural Bharatpur district of Rajasthan. Eligible subjects in the 25 selected clusters were enumerated through a door-to-door household survey and invited to village sites for visual acuity testing and eye examination early in 1999. The principal cause of reduced central vision was identified for eyes that had visual acuity worse than 6/18. Independent replicate testing for quality assurance monitoring took place in participants with reduced vision and in a sample of those with normal vision in five of the study clusters. MAIN OUTCOME MEASURES: Presenting and best-corrected visual acuity and lens status. RESULTS: A total of 4728 eligible persons in 2821 households were enumerated, and 4284 (90.6%) were examined. The prevalence of presenting and best-corrected visual acuity worse than 6/60 in both eyes was 11.9% (95% confidence interval: 10.0%-13.9%) and 6.1% (95% CI: 4.7%-7.4%), respectively. Presenting blindness was associated with increasing age, female gender, lack of schooling, and rural residence. Cataract was the principal cause of blindness in one or both eyes in 67.5% of blind persons, with uncorrected aphakia and other refractive error affecting 18.4% in at least one eye. The prevalence of cataract surgery was 12.8% (95% CI: 11.6%-14.0%), with an estimated 65.7% of the cataract blind operated on; low surgical coverage was associated with lack of schooling. CONCLUSIONS: Blindness, particularly blindness because of cataract, continues to be a significant problem among the elderly living in remote areas of rural northwest India. Increased attention should be given to reaching women and the illiterate.     

Blind registrations in Western Australia: a five-year study

This paper reports the annual blind certification by the Association for the Blind, Western Australia, for five consecutive years, to December 1988. The data are analysed with a view to obtaining minimum figures for incidence of the major causes of blindness in this state.     

广州市盲校学生致盲及低视力原因调查

目的:调查盲校学生盲和低视力的原因,以确定潜在的可预防性和可治疗性因素。方法:采用世界卫生组织防盲计划儿童盲及低视力眼检查记录表,对2004年广州市盲校学生盲及低视力情况进行调查,并分析其原因。结果:177名4～33岁(平均13.5岁)学生,男:女为2.1︰1,视力为无光感者55人(31.1%),<0.05者96人(54.2%),<0.1者15人(8.5%),不合作或精神障碍者11人(6.2%)。致盲及低视力的原因依次为早产儿视网膜病变67人(37.9%),视神经萎缩,眼球萎缩及原因不明,视网膜变性分别为15人(8.5%),先天性青光眼9人(5.1%),先天性黄斑异常8人(4.5%),视网膜脱离和先天性白内障分别7人(3.9%),先天性小眼球和角膜病变分别为5人(2.8%),其他24人(13.6%)。其中以早产儿视网膜病变为最重要的致盲因素(占37.9%),分别占≤10岁组的57.7%,≤15岁组的33.9%,≤20岁组的28.6%,大于20岁组的14.3%;以及占无光感组52.7%,视力<0.05组31.3%,不合作或精神障碍组63.6%。可避免性盲(包括早产儿视网膜病变,屈光不正,白内障术后弱视)73人(41.2%),仍有视力提高可能的治疗价值者14人(7.9%)。结论:早产儿视网膜病变是近年来盲童主要致盲原因;加强对早产儿围产期的监测,早发现,早治疗,有助减少致盲的可能。     

Gender and blindness: a meta-analysis of population-based prevalence surveys

BACKGROUND: Many individual surveys of blindness have reported slightly higher rates of blindness for women. In order to gain a continent-by-continent and global sense of the burden of blindness by sex we conducted a meta-analysis of published, population-based surveys of blindness. METHOD: Published reports were collected using a predetermined search protocol involving commercial electronic databases, hand-searching of references and direct contact with researchers. Studies were included that were population-based, included clinical examination and had a minimum sample size of 1000. The studies were critically appraised to determine methodological rigour. Data were analysed using the Cochrane Collaboration Review Manager. RESULTS: The overall odds ratio (age-adjusted) of blind women to men is 1.43 (95% CI 1.33–1.53), ranging from 1.39 (95% CI 1.20–1.61) in Africa, 1.41 (95% CI 1.29–1.54) in Asia, and 1.63 (95% CI 1.30–2.05) in industrialised countries. There was good homogeneity of findings from Africa, Asia, and the industrialised countries. Globally, women bear excess blindness compared to men. In these surveys, overall, women account for 64.5% of all blind people. The excess of blindness in women was marked among the elderly and not due only to differential life expectancy. CONCLUSION: The excess burden of blindness among women is likely due to a number of factors, which are different in industrialised countries compared to developing countries. Particular attention to gender differences in blindness is needed in the creation of targets for blindness reduction and in the development of interventions.     

Blindness and vision impairment in the elderly of Papua New Guinea

BACKGROUND: To estimate the magnitude and causes of blindness and vision impairment in Papua New Guinea for service delivery planning and ophthalmic education development. METHODS: Using the World Health Organization standardized Rapid Assessment of Cataract Surgical Services protocol, a population-based cross-sectional survey was conducted in 2005. By systematic, two-stage cluster random sampling, 39 clusters each of 30 people aged 50 years and over were selected from urban and rural locations. A cause of vision loss was determined for each eye with a presenting visual acuity worse than 6/18. RESULTS: Of the 1191 people enumerated, 1174 were examined (98.6%). The 50 years and older age-gender adjusted prevalence of vision impairment (presenting visual acuity less than 6/18 in the better eye) was 29.2% (95% Confidence Interval [CI]: 27.6, 35.1, Design Effect [deff] = 2.3). That of functional blindness (presenting visual acuity less than 6/60 in the better eye) was 8.9% (95% CI: 8.4, 12.0, deff = 1.2), and of World Health Organization blindness (but presenting, rather than best corrected, visual acuity of less than 3/60 in the better eye) was 3.9% (95% CI: 3.4, 6.1, deff = 1.0). Uncorrected refractive error (13.1%, 95% CI: 11.3, 15.1, deff = 1.2) and cataract (7.4%, 95% CI: 6.4, 10.2, deff = 1.3) were leading causes of vision impairment, age-gender adjusted. Cataract was the most common (age-gender adjusted 6.4%, 95% CI: 5.1, 7.3, deff = 1.1) cause of functional blindness. On bivariate analysis, increasing age (P < 0.001), illiteracy (P < 0.001) and unemployment (P < 0.001) were associated with functional blindness. Gender was not. CONCLUSIONS: The identification and treatment of refractive error and cataract need to be priorities for eye health services in Papua New Guinea if the burden of vision impairment and blindness is to be diminished. The education of community and hospital eye care providers, whether medical, nursing or other cadres, must emphasize these. Eye care services must be structured and provided to allow and encourage accessibility and uptake, with satisfactory treatment outcomes for these conditions.