Abstract
Purpose: :
To report the prevalence and causes of visual impairment among adults in a Danish suburban population with a focus on diabetes.
Methods: :
Randomly selected participants from the General Suburban Population Study in Næstved, Denmark underwent visual acuity testing with a Nidek Auto Refractometer 360-A. This was followed by an EDTRS Eye Chart exam if vision was less than 20/25 in one or both eyes. Additionally, retinal photography of both eyes, Hirschberg’s test and Ishihara pseudoisochromatic test were performed in all participants. The cause of decreased visual acuity was determined using a combination of the participant's ophthalmologic record, interview responses, retinal photographs and ophthalmologic examination. Visual impairment was defined as best-corrected visual acuity of < 20/40. Bilateral visual impairment was defined from the better eye and unilateral impairment from the worse eye.
Results: :
Among 1949 preliminary participants (age range 20-92 years, mean 55.2) the prevalence of bilateral visual impairment was 0.36% (7/1949), with age-related macular degeneration in 0.15% (3/1949) and cataract in 0.10% (2/1949). The prevalence of unilateral visual impairment was 4.10% (80/1949). The main causes of unilateral visual impairment among our participants were: 1. Amblyopia in 1.49% (29/1949), 2. Cataract in 0.56% (11/1949), 3. Age-related macular degeneration in 0.21% (4/1949), 4. Trauma in 0.21% (4/1949), 5. Retinal vein occlusion in 0.15% (3/1949), 6. Macular hole in 0.15% (3/1949) and 7. Diabetic retinopathy in 0.15% (3/1949). The prevalence of diabetes in our population was 6.24% (120/1923), defined as HgbA1c ≥ 6.5% or a self-reported diagnosis of diabetes if HbgA1c < 6.5%.
Conclusions: :
Our preliminary results indicate that bilateral visual impairment is rare among adults in Næstved, Denmark. Amblyopia is the leading cause of unilateral visual impairment in our population. Diabetic retinopathy was a surprisingly rare cause of visual impairment, despite the prevalence of diabetes in this population.
Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • diabetes • amblyopia