The utility of relative afferent pupillary defect as a screening tool for glaucoma: prospective examination of a large population-based study in a south Indian population.

BACKGROUND: Previous authors have suggested that an afferent pupillary defect (APD) may serve as an effective screening tool for some specific eye diseases, especially glaucomatous optic neuropathy, since the disease usually presents asymmetrically. Its success as a screening tool for glaucoma has never been previously prospectively evaluated in a large population. METHODS: In this study, the authors carry out assessments for the presence of APD as it relates to the diagnosis of glaucoma in an existing population-based eye study in southern India. The authors calculate the sensitivity and specificity for APD, both at the level of a village/household screening and in a more comprehensive/hospital setting, as it pertains to its ability to predict glaucomatous optic neuropathy. RESULTS AND DISCUSSION: The authors find that APD assessed via the swinging flashlight test is a poor screening tool for glaucoma in this setting.

Population-based prevalence of uveitis in Southern India.

PURPOSE: To estimate the prevalence of uveitis in rural Tamil Nadu, India. METHODS: Cluster sampling identified a population-based sample of 5150 persons ages 40 years and older, representative of three districts in Tamil Nadu, India. Each received a comprehensive dilated ocular examination by an ophthalmologist, and results were registered on forms requiring responses about the presence of ocular inflammatory signs and inflammatory diagnoses. Potential uveitis cases were confirmed by consensus of two uveitis specialists, upon review of study and medical records. Crude prevalence rates and prevalence rates age-adjusted to reflect the 2001 Tamil Nadu census population were calculated. RESULTS: Crude and age-adjusted prevalence rates for endogenous uveitis were 310/100,000 and 317/100,000. The corresponding rates for all ocular inflammation were 450 and 467/100,000. Males tended to have a greater prevalence than females in this population, and older persons tended to have higher prevalence than younger persons. The majority of cases of posterior uveitis and infectious endophthalmitis were visually compromised, but few among the cases of other forms of ocular inflammation were visually impaired. CONCLUSIONS: The results suggest that nearly one in 200 persons in rural, South India has been affected by ocular inflammation in at least one eye by mid to late adulthood, about one in 330 if cases related to surgery or trauma are not included. Postsurgical endophthalmitis and posterior uveitis were associated with a high rate of vision loss. These results indicate that uveitis is an important cause of ocular morbidity and of vision loss in this population.

Exposure to indoor biomass fuel and tobacco smoke and risk of adverse reproductive outcomes, mortality, respiratory morbidity and growth among newborn infants in south India.

BACKGROUND: Exposure to indoor air pollution due to open burning of biomass fuel is common in low- and middle-income countries. Previous studies linked this exposure to an increased risk of respiratory illness, low birth weight (LBW) and other disorders. We assessed the association between exposure to biomass fuel sources and second-hand tobacco smoke (SHTS) in the home and adverse health outcomes in early infancy in a population in rural south India. METHODS: A population-based cohort of newborns was followed from birth through 6 months. Household characteristics were assessed during an enrolment interview including the primary type of cooking fuel and smoking behaviour of household residents. Follow-up visits for morbidity were carried out every 2 weeks after delivery. Infants were discharged at 6 months when anthropometric measurements were collected. RESULTS: 11 728 live-born infants were enrolled and followed, of whom 92.3% resided in households that used wood and/or dung as a primary source of fuel. Exposure to biomass fuel was associated with an adjusted 49% increased risk of LBW, a 34% increased incidence of respiratory illness and a 21% increased risk of 6-month infant mortality. Exposed infants also had 45 and 30% increased risks of underweight and stunting at 6 months. SHTS exposure was also associated with these adverse health outcomes except for attained growth. CONCLUSIONS: Open burning of biomass fuel in the home is associated with significant health risks to the newborn child and young infant. Community-based trials are needed to clarify causal connections and identify effective approaches to reduce this burden of illnesses.

Risk factors for maternal night blindness in rural South India.

PURPOSE: This study aimed to identify risk factors associated with maternal night blindness in rural South India. METHODS: At delivery, women enrolled in a population-based trial of newborn vitamin A supplementation were asked whether they were night blind at any time during the pregnancy. Multivariate logistic regression was used to identify socioeconomic, demographic, and pregnancy-related factors associated with maternal night blindness. RESULTS: Women reported night blindness in 687 (5.2%) of 13,171 pregnancies. In a multivariate model, having a concrete roof (Odds Ratio (OR): 0.60, 95% Confidence Interval (CI): 0.47, 0.78), religion other than Hindu (OR: 0.46, 95% CI: 0.27, 0.76), maternal literacy (OR: 0.58, 95% CI: 0.49, 0.69), and maternal age from 25 to 29 years (OR: 0.68, 95% CI: 0.50, 0.93) were associated with a lower risk of night blindness in pregnancy. The odds of night blindness were higher for those leasing rather than owning land (OR: 1.78, 95%CI: 1.08, 2.93), parity 6 or more compared to 0 (OR: 2.11, 95% CI: 1.09, 4.08), and with twin pregnancies (OR: 3.23, 95% CI: 1.93, 5.41). Factors not associated with night blindness in the multivariate model were other markers of socioeconomic status such as electricity in the house, radio and television ownership, type of cooking fuel and household transportation, and number of children under 5 years of age in the household. CONCLUSIONS: Maternal night blindness was prevalent in this population. Being pregnant with twins and of higher parity put women at higher risk. Maternal literacy and higher socioeconomic status lowered the risk.

Relationship between vision impairment and eye disease to vision-specific quality of life and function in rural India: the Aravind Comprehensive Eye Survey.

PURPOSE: To determine the impact of vision impairment and eye diseases on vision-specific quality of life and visual function in an older population of rural southern India. METHODS: Presenting and best-corrected visual acuity and burden of eye diseases were determined in a population aged 40 years and older, identified through a random cluster sampling strategy from 50 villages of rural south India. A questionnaire validated previously for use in this population was used to ascertain quality of life and visual function. Visual acuity measurements were obtained with illiterate E Early Treatment Diabetic Retinopathy Study (ETDRS) charts. Cataract was graded and defined based on the Lens Opacities Classification System (LOCS) III. Macular degeneration was defined based on the classification system proposed by the International ARM Epidemiologic Study Group. Glaucoma was defined based on results of clinical examinations including optic disc and visual fields. Analyses were performed to explore the relationship of overall and subscale quality-of-life and visual function scores with presenting acuity in the better-seeing eye, specific eye diseases, and demographic variables. RESULTS: Information on quality of life and visual function were available for 5119 (99.4%) of 5150 study subjects. The mean presenting visual acuity in the better eye was 0.76 +/- 0.53 logMAR (logarithm of the minimum angle of resolution) units. Age, education, occupation, presenting acuity in the better eye, and presence of a cataract, glaucoma, or refractive error were independently associated with overall quality-of-life and vision function scores. After adjustment for demographic variables and ocular disease, persons with vision impairment or bilateral blindness based on presenting visual acuity had lower scores across all domains of quality of life and vision function. Scores for subscales of quality-of-life and vision function domains were significantly lower among those with age-related cataract and glaucoma compared with persons without those eye diseases. CONCLUSIONS: Presenting vision in the better eye was associated with quality of life and vision function in this older population of rural south India. Subjects with glaucoma and age-related cataract had an associated decrease in quality of life and vision function, independent of presenting visual acuity in the better eye.

Female reproductive factors and eye disease in a rural South Indian population: the Aravind Comprehensive Eye Survey.

PURPOSE: To determine the potential associations of female reproductive factors with age-related cataract, open-angle glaucoma, macular degeneration, and myopia in an older population of rural south India. METHODS: This was a population-based, cross-sectional study of older adults in rural south India identified through a cluster sampling technique. Histories relating to female reproductive factors were ascertained through a questionnaire administered by trained workers. Detailed ocular examinations including automated perimetry were performed on all participants at a base hospital to arrive at a diagnosis of ocular morbidity. RESULTS: The study achieved a high response rate (93.0%), with examinations performed on 5150 of the eligible 5539 persons aged 40 years or more. Age at menarche was available for 2797 (98.6%) of the women and age at natural menopause for 1841 (98.0%) of 1878 women who were postmenopausal. The mean age at menarche was 14.8 +/- 1.8 years, and the mean age at menopause was 43.4 +/- 3.9 years. The mean duration of endogenous estrogen exposure was 28.4 +/- 4.3 years. The median number of pregnancies was 4 (mean, 4.3 +/- 2.6; range, 0-16). Older age at menarche (>or=14 years) was associated with reduced risk for age-related cataract and myopia, and greater risk for macular degeneration. Neither age at menopause nor duration of endogenous estrogen exposure was associated with any of the ocular diseases studied. Parity was not associated with any of the ocular diseases studied in a multivariate model. CONCLUSIONS: Female reproductive factors do not appear to influence age-related cataract, open-angle glaucoma, macular degeneration or myopia significantly in rural south India.

Ocular trauma in a rural south Indian population: the Aravind Comprehensive Eye Survey.

PURPOSE: To determine the rate of ocular trauma in a rural population of southern India and its impact on vision impairment and blindness. METHODS: A population-based cross-sectional study of 5150 persons 40 years or older in a randomly chosen rural population of 3 districts of southern India. Prospective information on trauma, type and agent of injury, setting of injury, and details of treatment sought for the last episode was recorded with questionnaires after face-to-face interviews. All interviewed subjects underwent a comprehensive ocular examination, including vision estimations, slit-lamp biomicroscopy examinations, and dilated posterior segment examinations. RESULTS: We elicited a history of ocular trauma in either eye from 229 (4.5%) persons, including 21 (0.4%) persons with bilateral ocular trauma. Blunt injuries (n = 124; 54.9%) were the major cause for trauma reported in this population. The most common setting where the ocular trauma occurred was during agricultural labor (n = 107; 46.9%). Nearly three quarters (n = 170; 74.2%) of those reporting ocular trauma sought treatment from an eye specialist (n = 104; 57.8%) and one fifth (n = 37; 20.6%) from a traditional healer. The age-adjusted (adjusted to the population estimates for India for the year 2000) prevalence for blindness in any eye caused by trauma was 0.8% (95% confidence interval [CI], 0.4-1.1). The odds ratios (OR) for trauma were higher for males (OR, 2.2; 95% CI, 1.6-3.0) and laborers (OR, 1.7; 95% CI, 1.2-2.4) and lower for literates (OR, 0.7; 95% CI, 0.5- 0.9). Seeking treatment from a traditional eye healer for trauma was not associated with vision impairment (OR, 1.0; 95% CI, 0.3-3.2) or with blindness (OR, 3.4; 95% CI, 0.2-56.5). CONCLUSIONS: Eye care programs may need to consider ocular trauma as a priority in this population, because the lifetime prevalence of ocular trauma is higher than that reported for glaucoma, age-related macular degeneration, or diabetic retinopathy from this population. Simple measures such as education regarding the use of protective eyewear could possibly significantly decrease this preventable cause of visual disability.

Prevalence of vitreoretinal disorders in a rural population of southern India: the Aravind Comprehensive Eye Study.

OBJECTIVE: To determine the magnitude of vitreoretinal disorders in a rural southern Indian population. METHODS: Cluster sampling was used to identify individuals 40 years and older in Tamil Nadu in southern India. Demographic details, vision measurement and refraction using logMAR charts, anterior segment slitlamp examination, dilated posterior segment slitlamp examination using a 78-diopter (D) lens, and indirect ophthalmoscopy using a 20-D lens were performed. RESULTS: Complete retinal data were available for 4917 (95.5%) of the 5150 persons examined. The prevalence of any vitreoretinal disorder was 10.4% (95% confidence interval [CI], 9.5%-11.3%). The population prevalence of bilateral blindness among persons with vitreoretinal disorders was 0.3% (95% CI, 0.2%-0.5%). The prevalence of diabetic retinopathy was 0.5% (95% CI, 0.3%-0.7%) in the general population and 10.5% (95% CI, 6.5%-14.5%) in patients with diabetes mellitus. Only 6.7% of individuals with diabetic retinopathy had previous ophthalmic examinations. The prevalences of early and late age-related macular degeneration were 2.7% (95% CI, 2.2%-3.2%) and 0.6% (95% CI, 0.4%-0.8%), respectively. CONCLUSIONS: Vitreoretinal diseases appear to be a major public health problem in India. Emphasis on diabetic screening, diabetic therapy, and appropriate laser therapy of diabetic retinopathy must be explored.

The utilization of eye care services by persons with glaucoma in rural south India.

PURPOSE: To determine utilization of eye care services, in particular those relating to glaucoma, in a rural population of southern India aged 40 years or older. METHODS: A total of 5,150 subjects aged 40 years or older selected through a random cluster sampling technique from three districts in southern India underwent detailed ocular examinations for vision impairment, blindness, and ocular morbidity. Information regarding previous use of eye care services was collected from this population through a questionnaire administered by trained social workers prior to ocular examinations. RESULTS: One thousand eight hundred and twenty-seven persons (35.5%) gave a history of prior eye examinations, primarily from a general hospital (n = 1,073, 58.7%). Increasing age and education were associated with increased utilization of eye care services. Among the 3,323 persons who had never sought eye care, 912 (27.4%) had felt the need to have an eye examination but did not do so. Only one third of persons with vision impairment, cataracts, refractive errors, and glaucoma had previously utilized services. Of the 64 subjects diagnosed as having primary open-angle glaucoma, 32 (50%) had previously seen an ophthalmologist, but none had had an eye examination within 1 year before the study. Only six (19%) of the 32 had been diagnosed as having glaucoma (9% of all subjects found to have glaucoma in the survey). Thirteen (20.3%) of the 64 subjects were blind in either eye due to glaucoma, including one person who was bilaterally blind. CONCLUSIONS: A large proportion of persons in a rural population of southern India who require eye care are currently not utilizing existing eye care services. Strategies to improve the uptake of services are required to reduce the burden of blindness due to glaucoma in southern India.

Quality of life after community-based rehabilitation for blind persons in a rural population of South India.

This study aimed to determine the impact of community-based rehabilitation on the quality of life of blind persons in a rural south Indian population. We performed a population-based survey followed by clinical examinations to identify blind persons in a rural south Indian population. Pre-and-post rehabilitation quality of life of 159 blind persons aged 15 years or above was ascertained through a questionnaire previously validated for use in this population. Post-rehabilitation quality-of-life scales showed some improvement for 151 (95.0%) subjects. The additional benefit from rehabilitation was greatest for the self-care and mobility subscales, ranging from 24.6% to 30.0% for the self care subscale and 37.6% to 44.3% for the mobility subscale with effect sizes of 21.5 and 2.38 respectively. Overall quality of life scores were not significantly different between those who did and did not receive economic rehabilitation (P = 0.1). Blind persons in this rural population benefited considerably from rehabilitation services even if economic rehabilitation is not provided. Initiatives against blindness need to consider rehabilitation of the blind as a priority.

Utilization of community-based rehabilitation services for incurably blind persons in a rural population of southern India.

PURPOSE: To identify barriers in utilisation of community based rehabilitation (CBR) services for incurably blind persons in rural South India. METHODS: A community-based rehabilitation programme for incurably blind persons was initiated in Theni district of southern Tamil Nadu in south India. After door-to-door enumeration and preliminary ocular screening by trained workers at the village, identified blind persons were categorised as either curable or incurable by an ophthalmologist. Trained workers provided rehabilitation, including mobility training (OM), training to perform activities of daily living (ADL), and economic rehabilitation for the incurably blind in their respective villages. RESULTS: Of the 460,984 persons surveyed, 400 (0.09%) were certified as incurably blind including 156 (39.00%) persons blind from birth. Social rehabilitation was provided for 268 (67.00%) incurably blind persons. Economic rehabilitation was provided to 96 persons, and integrated education to 22 children. Nearly one-fifth (n=68, 17.00%) of incurably blind persons refused the services provided. The major reasons for refusal included old age and other illnesses (41.18%), and multiple handicaps (19.12%). Twenty-seven (6.75%) persons had either migrated or died, and 29 (7.25%) persons were already able to function independently. CONCLUSION: Although CBR programmes provide useful services to the incurably blind, a better understanding of barriers is required to improve service utilisation. Developing a standardised data collection format for every CBR programme can result in the creation of a national database of ophthalmic diseases.

Lens opacities in a rural population of southern India: the Aravind Comprehensive Eye Study.

OBJECTIVES: To determine the prevalence of lens opacities in an older population in rural southern India. METHODS: A cross-sectional study of 5150 persons aged 40 years and more who were selected as part of a representative sample from three southern districts of the state of Tamil Nadu in southern India. All lenses were graded and classified for opacities and other disorders by slit lamp after pupillary dilation, using the Lens Opacification Classification System (LOCS) III and standard photographs. Definite cataract was defined as either LOCS III nuclear opalescence of grade 3.0 or more and/or cortical cataract of grade 3.0 or more and/or posterior subcapsular cataract (PSC) of grade 2.0 or more. RESULTS: Definite cataract was present in one or both eyes in 2499 (47.5%) of 5150 subjects. The age-adjusted prevalence (adjusted to U.S. population estimates for 2000) of definite cataract in this population was 61.9% (95% CI, 60.6-6.3). The prevalence was significantly lower in men (P=0.0002). In those eyes with cataracts, nuclear cataract (59.7%) was most common, and cortical cataract was present in 20.0% and PSC in 24.3%. Cataract surgery had been performed in 9.4% persons, including 3.0% who had bilateral surgery for cataracts. Best corrected visual acuity was less than 6/60 in 3.7% of aphakic eyes and in 0.8% of pseudophakic eyes. CONCLUSIONS: The higher age-adjusted prevalence and relatively early onset of age-related cataract in this population suggest that the cataract-centered approach to minimizing preventable blindness, adopted by the National Program for Prevention of Blindness in India, is appropriate.