Risk Factors For Visual Impairment Research Articles

Visual acuity outcomes in pediatric glaucomas

To evaluate and compare the visual acuity prognosis in the various pediatric glaucoma subtypes and to determine risk factors for vision loss. The medical records of pediatric glaucoma patients from 2000 to 2010 at Children's Hospital of Philadelphia were retrospectively reviewed. Visual acuities, surgeries, glaucoma subtype, and etiology of vision impairment were recorded. Univariate and multivariate analyses were performed to determine the risk factors for visual impairment. A total of 133 eyes (36.8% primary congenital glaucoma, 28.6% aphakic glaucoma, 12.0% glaucoma associated with anterior segment dysgenesis, 12.0% Sturge-Weber glaucoma) of 88 patients were included. At last follow-up (median length, 5 years), 46.6% eyes achieved excellent (≥20/70) visual acuity. Of the glaucoma subtypes, primary congenital glaucoma conferred the best visual prognosis, with 69.4% eyes with excellent (≥20/70) visual acuity at final follow-up. Factors most associated with visual impairment (<20/200) were unilateral disease, multiple surgeries, poor vision at diagnosis, and other ocular comorbidities. The most common primary etiology for vision impairment was amblyopia (54.9%). Patients with glaucoma early in life appear to have a better visual acuity prognosis than previously reported, with those with primary congenital glaucoma faring better than other glaucoma subtypes. Recognition of risk factors for visual impairment can better guide clinical management and counseling of patients.

Prevalence and Risk Factors for Visual Impairment in Preschool Children: The Sydney Paediatric Eye Disease Study

To assess the prevalence and associations of visual impairment (VI) in preschool children. Cross-sectional, population-based study. A total of 2461 children (73.8% participation rate), aged 6 to 72 months, were examined in the Sydney Paediatric Eye Disease Study during 2007-2009; of whom 1188, aged 30 to 72 months, with complete visual acuity (VA) data in both eyes, were included in this report. Measurement of VA was attempted on all children using the Electronic Visual Acuity (EVA) system or a logarithm of the minimum angle of resolution (logMAR) chart. Visual impairment was defined as presenting VA <20/40 in children aged ≥48 months and <20/50 in those aged <48 months. Post-cycloplegic refraction was measured, and myopia was defined as spherical equivalent (SE) ≤-0.50 diopters (D), hyperopia was defined as SE ≥2.00 D, astigmatism was defined as cylinder ≥1.00 D, and anisometropia was defined as SE difference ≥1.00 D between 2 eyes. Ethnicity, birth parameters, and sociodemographic information were collected in questionnaires completed by parents. Visual impairment prevalence and its associations with child demographic factors and birth parameters. Visual impairment was found in 6.4% of the worse eye and 2.7% of the better eye in our sample. Refractive errors (69.7%) and amblyopia (26.3%) were the principal causes of VI in the worse eye. Astigmatism (51.3%) and hyperopia (28.9%) were the main refractive errors causing VI. In regression analysis controlling for other factors, VI was independently associated with low birthweight of <2500 g (odds ratio 2.4, 95% confidence interval, 1.1-5.3), but not with age, gender, ethnicity, or measures of socioeconomic status (P > 0.05). Visual impairment in at least 1 eye was found in 6.4% of Australian preschool children, with bilateral VI found in 2.7%. Uncorrected refractive errors and amblyopia were the principal ocular conditions associated with VI. Low birthweight was a significant risk factor independent of age, gender, and ethnicity. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Sociodemographic, Lifestyle, and Medical Risk Factors for Visual Impairment in an Urban Asian Population

To describe the associations between sociodemographic, lifestyle, and medical risk factors and visual impairment in a Southeast Asian population. Population-based cross-sectional study of 3280 (78.7% response rate) Malay Singaporeans aged 40 to 80 years. Participants underwent a standardized interview, in which detailed sociodemographic histories were obtained, and clinical assessments for presenting and best-corrected visual acuity. Visual impairment (logMAR > 0.30) was classified as unilateral (1 eye impaired) or bilateral (both eyes impaired). Analyses used multivariate-adjusted multinomial logistic regression. Older age and lack of formal education was associated with increased odds of both unilateral and bilateral visual impairment based on presenting and best-corrected visual acuity. The odds doubled for each decade older, and lower education increased the odds 1.59- to 2.83-fold. Bilateral visual impairment was associated with being unemployed (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.30-2.60), widowed status (OR, 1.51; 95% CI, 1.13-2.01), and higher systolic blood pressure (OR, 1.96; 95% CI, 1.44-2.66). Diabetes was associated with unilateral (OR, 1.47; 95% CI, 1.10-1.95) and bilateral (OR, 1.69; 95% CI, 1.23-2.32) visual impairment using best-corrected visual acuity. Older age, lower education, unemployment, being widowed, diabetes, and hypertension were independently associated with bilateral visual impairment. Public health interventions should be targeted to these at-risk populations.

White-Matter Injury is Associated With Impaired Gaze in Premature Infants

Periventricular leukomalacia is a risk factor for visual impairment in children born prematurely. The impact of diffuse white-matter injury, as detected on magnetic resonance imaging, on early visual function is unknown. We developed two 5-point visual-gaze scores to analyze the association between this clinical assessment and white-matter injury in 93 premature neonates <34 weeks of gestational age at birth. Older postmenstrual age was associated with higher values of the two gaze scores. Infants with moderate or severe white-matter injury had lower scores than their peers without white-matter injury (0.41 points, 95% confidence interval of 0.13-0.69 for visual fixation score; and 0.70 points, 95% confidence interval of 0.30-1.10 for conjugate score, P < 0.005). Using the results from both scales, a score of >or=9 in an infant examined at >or=36 weeks postmenstrual age predicted normal white matter on magnetic resonance examination, with a sensitivity of 84% and a specificity of 100%. These preliminary findings suggest that white-matter injury affects visual function even before term equivalent postmenstrual age.

Prevalence of visual impairment in relation to the number of ophthalmologists in a given area: a nationwide approach

Sociological and economic risk factors of visual impairment have never been described in France at a national level as the association between the number of ophthalmologists per inhabitant and visual impairment prevalence. Two national surveys were pooled. First, 2075 institutions were selected at random from the French Health Ministry files. Second, a random, stratified sample of 356,208 citizens living in the community was selected. Blindness and low vision (LV) prevalence rates were estimated by age and gender. Geographical equities were estimated by logistic regression adjusted on age and occupational category. The association between ophthalmologist density and visual impairment prevalence rate was estimated per region. Interviews were completed with 14,603 (94.9%) of 15,403 randomly selected subjects in institutions, and 16,945 (77.8%) of 21,760 randomly selected subjects in the community. Three groups were defined from the interviews: low vision, blind, and control. Prevalence rates were LV 2.08% and blindness 0.12%. Both rates increased exponentially with age. No major difference was found with gender. Injury was the declared reason for both LV (12%) and blindness (12%). Large regional differences in prevalence persisted for LV after adjustment on age and occupation (ORs: 0.35 to 2.10), but not for blindness. Regions with ophthalmologists below the national per capita average were usually those with higher LV prevalence. An inverse correlation was found between ophthalmologist number and LV prevalence rates for subjects of similar age and socio-professional category. This denoted possible inequity in the provision of healthcare.

Prevalence of visual impairment in relation to the number of ophthalmologists in a given area: a nationwide approach

BackgroundSociological and economic risk factors of visual impairment have never been described in France at a national level as the association between the number of ophthalmologists per inhabitant and visual impairment prevalence.MethodsTwo national surveys were pooled. First, 2075 institutions were selected at random from the French Health Ministry files. Second, a random, stratified sample of 356,208 citizens living in the community was selected. Blindness and low vision (LV) prevalence rates were estimated by age and gender. Geographical equities were estimated by logistic regression adjusted on age and occupational category. The association between ophthalmologist density and visual impairment prevalence rate was estimated per region. Interviews were completed with 14,603 (94.9%) of 15,403 randomly selected subjects in institutions, and 16,945 (77.8%) of 21,760 randomly selected subjects in the community. Three groups were defined from the interviews: low vision, blind, and control.ResultsPrevalence rates were LV 2.08% and blindness 0.12%. Both rates increased exponentially with age. No major difference was found with gender. Injury was the declared reason for both LV (12%) and blindness (12%). Large regional differences in prevalence persisted for LV after adjustment on age and occupation (ORs: 0.35 to 2.10), but not for blindness. Regions with ophthalmologists below the national per capita average were usually those with higher LV prevalence.ConclusionAn inverse correlation was found between ophthalmologist number and LV prevalence rates for subjects of similar age and socio-professional category. This denoted possible inequity in the provision of healthcare.

Visual Acuity in a Community-dwelling Japanese Population and Factors Associated with Visual Impairment

The aim of this study was to describe the distribution of visual acuity and investigate the predictors of visual impairment in a Japanese population. Best-corrected visual acuity was measured in 2263 subjects aged 40-79 years randomly selected from a local community. Relations between visual impairment and possible risk factors were investigated. Among these subjects, 41 individuals (1.8%) were identified as visually impaired (best-corrected visual acuity in the better eye <0.5). Both sexes in the older age groups had a higher frequency of visual impairment (Mantel-Haenszel chi-square test: P<0.001). A multiple logistic regression indicated that an increase in age of 10 years [odds ratio (OR) 3.9; 95% confidence interval (CI) 2.3-6.7] and myopia (OR 2.9; 95%CI 1.4-6.0) were independent risk factors for visual impairment. Individuals with the highest level of education (college or higher) had a lower risk of visual impairment (OR 0.1; 95%CI 0-0.7) compared to individuals with the lowest level of education. As expected, visual impairment increased with advancing age, although the prevalence of visual impairment in our population was lower than in other surveys. Racial and regional differences and differences in study design may be responsible for discrepancies between surveys. It is noteworthy that myopia was a significant risk factor for visual impairment, although the reasons for this association are uncertain and need further investigation.

Refractive errors and visual impairment in 900 adults with intellectual disabilities in the Netherlands.

To collect data on refractive errors and visual impairment in adults with an intellectual disability (ID) in the Netherlands. A randomized sample of 2100 participants was drawn from a base population of 9000 adults with intellectual disabilities in the Netherlands. This article reports on the first 900 participants. All participants underwent a protocol-based on-site ophthalmological assessment carried out by skilled investigators. Co-operation was classified according to the number of tests that could be carried out reliably and was good or excellent in 80% of subjects, average in 13% and poor in 7%. Refraction could be reliably assessed in 505/900 (56%) subjects. There was an increased risk of visual impairment in all subgroups compared to the general Dutch population. Visual acuity (VA) was related to the level of ID, but refractive errors were not. New spectacles were prescribed in 106 cases (12%). Of 374 people in whom both monocular VA and the refractive error of the right eye could be reliably assessed, 153 (41%) had a pretest prescription, 16 (10%) of which we found to be inadequate. Of the 221 participants without a pretest prescription, 41 (19%) benefited from correction. Only 38/84 (45%) subjects aged 50 years or older, who could benefit from correction for near vision, had near spectacles. New correction increased the mean distant VA significantly from 0.44 to 0.65 (p < 0.0005). With some adaptations, visual screening is feasible in a majority of adults with ID. Visual impairment and refractive errors are much more prevalent in adults with ID than in the normal population. Accurate spectacle correction resulted in significant improvement in distant VA.

A small number of older type 2 diabetic patients end up visually impaired,: by C. Hansson-Lundblad, K. Holm, C. D. Agardh, and E. Agardh. Acta Ophthalmol Scan 80:310–5, 2002

Purpose: The present study describes the prevalence of visual impairment and blindness in a geographically defined population 8 years after the introduction of a screening programme in 1987 for early detection of sight-threatening diabetic retinopathy. Methods: Of 374 patients with diabetes, comprising 2.6% of the population in the study community, 72% were examined with fundus photography or biomicroscopy during 1994-95. These patients form the basis of this study. The screening programme was fulfilled by 93% of subjects, all of whom underwent ophthalmic examinations at least every other year. A total of 79 eyes in 52 patients received photocoagulation for macular oedema alone or in combination with severe non-proliferative or proliferative retinopathy. Results: Eight years after the implementation of the programme, only three patients, all with type 2 diabetes (diabetes diagnosed at or after 30 years of age), had visual acuity ≤ 0.1. The total number of eyes with visual acuity ≤ 0.5 was higher in insulin-treated type 2 diabetic patients (n = 20) than in those on oral treatment (n = 5) or diet treatment only (n = 1) (p = 0.006 in both cases). The only independent risk factor for visual impairment in eyes with sight-threatening retinopathy was age. Conclusion: A small number of older type 2 diabetic patients end up with visual impairment due to unsuccessful photocoagulation of macular oedema.

A small number of older type 2 diabetic patients end up visually impaired despite regular photographic screening and laser treatment for diabetic retinopathy

The present study describes the prevalence of visual impairment and blindness in a geographically defined population 8 years after the introduction of a screening programme in 1987 for early detection of sight-threatening diabetic retinopathy. Of 374 patients with diabetes, comprising 2.6% of the population in the study community, 72% were examined with fundus photography or biomicroscopy during 1994-95. These patients form the basis of this study. The screening programme was fulfilled by 93% of subjects, all of whom underwent ophthalmic examinations at least every other year. A total of 79 eyes in 52 patients received photocoagulation for macular oedema alone or in combination with severe non-proliferative or proliferative retinopathy. Eight years after the implementation of the programme, only three patients, all with type 2 diabetes (diabetes diagnosed at or after 30 years of age), had visual acuity < or = 0.1. The total number of eyes with visual acuity < or = 0.5 was higher in insulin-treated type 2 diabetic patients (n = 20) than in those on oral treatment (n = 5) or diet treatment only (n = 1) (p = 0.006 in both cases). The only independent risk factor for visual impairment in eyes with sight-threatening retinopathy was age. A small number of older type 2 diabetic patients end up with visual impairment due to unsuccessful photocoagulation of macular oedema.

Prevalence of visual and hearing impairment in a Dutch institutionalized population with intellectual disability.

A screening of hearing and visual function was performed using clinical assessment methods in a Dutch institutionalized population of 672 people with mild to profound intellectual disability (ID). Because the studied population was not comparable to the total Dutch population with ID, subgroups were distinguished according to level of ID, age younger and older than 50 years, and the presence or absence of Down's syndrome (DS). The prevalences of both hearing and visual impairment were considerably increased in all subgroups, as compared with the general population. In the least affected group, i.e. those < 50 years with a mild or moderate ID by other causes than DS, the prevalences of hearing and visual impairment were 21% and 4%, respectively (as opposed to 2-7% and 0.2-1.9% in the general Dutch population <50 years, respectively). The prevalence of hearing impairment showed a sharp and highly significant increase in individuals with DS and subjects > or = 50 years. To a lesser extent, young adults with severe or profound ID had an increased risk of hearing impairment. Visual impairment and blindness were specifically highly prevalent in people with severe or profound ID (51% < 50 years of age). Down's syndrome and an age > or = 50 years were also significant risk factors for visual impairment. There was an alarmingly high prevalence of combined sensory impairment, especially in those with severe or profound ID (20%). Although hearing impairment had been diagnosed prior to this screen in 138 people and visual impairment in 65 individuals, a first diagnosis of hearing impairment was made in 128 subjects and of visual impairment in 90 cases. This highlights the tendency for sensory impairments to go unnoticed in people with ID, which is not restricted to those with severe or profound ID. Therefore, the present authors stress the importance of regular screening as outlined in the existing IASSID international consensus statement.

Risk Factor Assessment and Prognosis of Eye Involvement in Behçet's Disease in Turkey

Behcet's disease (BD) shows great regional differences in clinical manifestations and prognosis, including eye involvement. Thus, it is hard to predict in which patient the eyes will be involved and what the outcome will be. In this study we assessed various risk factors for eye involvement and attempted to predict the visual outcome in our patient population in Turkey. Data from a total of 224 patients with BD, diagnosed between 1982 and 1996, were analyzed retrospectively. A detailed physical examination and ophthalmologic work up were performed on each patient. Factors that might contribute to eye involvement were investigated, after which prognostic factors for vision were evaluated. Eighty-eight patients had eye involvement during a median follow-up of 32 months. The risk of involvement was highest within the first year of diagnosis. Young age was the most significant factor for eye involvement (P < 0.0001), but vascular thrombosis, central nervous system (CNS) involvement, and male gender were other risk factors (P < 0.001; P < 0.01; and P < 0.05, respectively). The most important determinant for the prognosis of vision was CNS involvement (P < 0.0001). Vascular thrombosis and an age of < or = 32 were other risk factors for visual impairment (P < 0.001 and P < 0.05, respectively). The risk of eye involvement and prognosis for vision were similar with different treatment regimens (P > 0.05). It is suggested that the first 2 years after diagnosis is the most critical period for eye involvement, and conventional forms of therapy generally are unsuccessful in preventing such involvement. It seems reasonable to treat patients who are at increased risk for eye involvement more aggressively, especially within the first 2 years of disease onset.