Abstract
Purpose: :
To describe the prevalence, causes and risk factors for visual impairment in a multi-ethnic Asian population with diabetes in Singapore.
Methods: :
Data were pooled from three population-based, cross-sectional studies of 3280 Malays, 3400 Indians and 2241 Chinese, aged 40-80+ years, living in Singapore. All participants underwent standardized clinical assessment and blood biochemical analyses. Diabetes was defined in persons with casual plasma glucose ≥200mg/dl (11.1mmol/l), self-reported physician-diagnosed diabetes, or the use of glucose lowering medication. Visual Impairment was defined using best corrected visual acuity (BCVA) and presenting visual acuity (PVA), according to US definitions. Blindness was defined as VA ≤20/200 and visual impairment as VA 20/200 in the better seeing eye.
Results: :
A total of 2208 Asian persons with diabetes were included in analyses (764 Malay, 1129 Indians and 315 Chinese). Based on PVA, the prevalence of bilateral blindness was 1.5% across the three groups and of bilateral visual impairment was 26.8%. Using BCVA, the prevalence of bilateral blindness was reduced to 0.9% and bilateral visual impairment to 9.0%. Cataract was the main cause of both presenting unilateral (37.3%) and bilateral (75.8%) blindness, as well as for bilateral visual impairment (43.5%). Other causes of presenting blindness and visual impairment included diabetic retinopathy (bilateral blindness 9.1%, unilateral blindness 9.8% and bilateral visual impairment 9.5%); glaucoma (bilateral blindness 6.1%, unilateral blindness 7.8%, bilateral visual impairment 1.2%) and age related macular degeneration (bilateral blindness 6.1%, unilateral blindness 3.9%, bilateral visual impairment 2.2%). In multivariate multinomial logistic regression, older age (OR1.07, p<0.001), male gender (OR 0.61, p=0.038), higher systolic blood pressure (OR 1.01, p=0.017), higher total cholesterol (OR 1.46, p<0.001), higher serum creatinine (OR 1.004, p<0.001), lower BMI (OR 0.96, p=0.044) and diabetes duration (OR 1.02, p=0.012) were associated with bilateral visual impairment. Ethnicity was not a significant risk factor.
Conclusions: :
Among Asian persons with diabetes in a developed country, cataract was the principal cause of both blindness and visual impairment, while diabetic retinopathy accounted for visual impairment among only 1 in 10 persons with diabetes. A broad eye disease screening and education strategy is needed to manage vision loss in persons with diabetes.
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • clinical (human) or epidemiologic studies: risk factor assessment • diabetes