PURPOSE: The prevalence of visual impairment due to uncorrected refractive error has not been previously studied in Canada. A population-based study was conducted in Brantford, Ontario. METHODS: The target population included all people 40 years of age and older. Study participants were selected using a randomized sampling strategy based on postal codes. Presenting distance and near visual acuities were measured with habitual spectacle correction, if any, in place. Best corrected visual acuities were determined for all participants who had a presenting distance visual acuity of less than 20/25. RESULTS: Population weighted prevalence of distance visual impairment (visual acuity <20/40 in the better eye) was 2.7% (n = 768, 95% confidence interval (CI) 1.8-4.0%) with 71.8% correctable by refraction. Population weighted prevalence of near visual impairment (visual acuity <20/40 with both eyes) was 2.2% (95% CI 1.4-3.6) with 69.1% correctable by refraction. Multivariable adjusted analysis showed that the odds of having distance visual impairment was independently associated with increased age (odds ratio, OR, 3.56, 95% CI 1.22-10.35; ≥65 years compared to those 39-64 years), and time since last eye examination (OR 4.93, 95% CI 1.19-20.32; ≥5 years compared to ≤2 years). The same factors appear to be associated with increased prevalence of near visual impairment but were not statistically significant. CONCLUSIONS: The majority of visual impairment found in Brantford was due to uncorrected refractive error. Factors that increased the prevalence of visual impairment were the same for distance and near visual acuity measurements.
PURPOSE: The prevalence of visual impairment due to uncorrected refractive error has not been previously studied in Canada. A population-based study was conducted in Brantford, Ontario. METHODS: The target population included all people 40 years of age and older. Study participants were selected using a randomized sampling strategy based on postal codes. Presenting distance and near visual acuities were measured with habitual spectacle correction, if any, in place. Best corrected visual acuities were determined for all participants who had a presenting distance visual acuity of less than 20/25. RESULTS: Population weighted prevalence of distance visual impairment (visual acuity <20/40 in the better eye) was 2.7% (n = 768, 95% confidence interval (CI) 1.8-4.0%) with 71.8% correctable by refraction. Population weighted prevalence of near visual impairment (visual acuity <20/40 with both eyes) was 2.2% (95% CI 1.4-3.6) with 69.1% correctable by refraction. Multivariable adjusted analysis showed that the odds of having distance visual impairment was independently associated with increased age (odds ratio, OR, 3.56, 95% CI 1.22-10.35; ≥65 years compared to those 39-64 years), and time since last eye examination (OR 4.93, 95% CI 1.19-20.32; ≥5 years compared to ≤2 years). The same factors appear to be associated with increased prevalence of near visual impairment but were not statistically significant. CONCLUSIONS: The majority of visual impairment found in Brantford was due to uncorrected refractive error. Factors that increased the prevalence of visual impairment were the same for distance and near visual acuity measurements.
Authors: Franziska Radicke; Thea Schwaneberg; Claudia Meinke-Franze; Clemens Jürgens; Hans Jörgen Grabe; Wolfgang Hoffmann; Frank Tost; Neeltje van den Berg Journal: BMC Geriatr Date: 2019-06-25 Impact factor: 3.921
Authors: Rupert R A Bourne; Jost B Jonas; Alain M Bron; Maria Vittoria Cicinelli; Aditi Das; Seth R Flaxman; David S Friedman; Jill E Keeffe; John H Kempen; Janet Leasher; Hans Limburg; Kovin Naidoo; Konrad Pesudovs; Tunde Peto; Jinan Saadine; Alexander J Silvester; Nina Tahhan; Hugh R Taylor; Rohit Varma; Tien Y Wong; Serge Resnikoff Journal: Br J Ophthalmol Date: 2018-03-15 Impact factor: 4.638