Abstract
Purpose :
Canada lacks high quality data on the prevalence of visual impairment. Our goal was to determine the prevalence and determinants of visual impairment in Canada.
Methods :
Data from 30,097 adults who took part in the Canadian Longitudinal Study on Aging Comprehensive Cohort were included. The participants were sampled using a combination of provincial health registries (14%) and random digit dialing (86%). Inclusion criteria included being between the ages of 45 and 85 years old, community-dwelling, and living near one of the 11 data collection sites across 7 Canadian provinces (Victoria, Vancouver, Surrey, Calgary, Winnipeg, Hamilton, Ottawa, Montreal, Sherbrooke, Halifax, and St. John’s). People were excluded if they were in an institution, living on a First Nations reserve, were a full-time member of the Canadian Armed Forces, did not speak French or English, or had cognitive impairment. Visual acuity was measured using the Early Treatment of Diabetic Retinopathy Study chart while participants wore their usual prescription for distance, if any. Visual impairment was defined as binocular acuity worse than 20/40. Logistic regression was used.
Results :
5.7% (95% Confidence Interval (CI) 5.4-6.0) of Canadian adults had visual impairment. A wide variation in the provincial prevalence of visual impairment was observed ranging from a low of 2.4% (95% CI 2.0-3.0) in Manitoba to a high of 10.9% (95% CI 9.6-12.2) in Newfoundland and Labrador. Factors associated with a higher odds of visual impairment included older age (odds ratio (OR)=1.07, 95% CI 1.06-1.08), lower income (OR=2.07 for those earning less than $20,000 per year, 95% CI 1.65-2.59), current smoking (OR=1.52, 95% CI 1.25-1.85), Type 2 diabetes (OR=1.20, 95% CI 1.03-1.41), and memory problems (OR=1.44, 95% CI 1.04-2.01).
Conclusions :
There is wide variation in the frequency of visual impairment across Canada. These data can be used by health policy planners, low vision rehabilitation providers, and eye care professionals to plan for the future eye care needs of Canada’s aging population.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.