How would you feel if you were driving your car and knew there was a good chance the person driving behind you on the highway might not have very good vision? Studies in other countries have shown that up to 10% of the population may have what is called uncorrected refractive error, vision loss that has not been corrected with appropriate lenses. CNIB decided to find out whether there are people walking around in Canada as well who have poor vision that could be corrected with eye glasses or contact lenses. We collaborated with the University of Waterloo, School of Optometry and decided to study the population of Brantford Ontario. Why Brantford? Well their population is reasonably representative of the Canadian population as a whole and they have good availability of optometric care.
Our researchers went to homes in Brantford that were selected based on a special sampling strategy and asked people to come and have their eyes examined by an eye doctor at the CNIB office in central Brantford. We were able to examine 768 people between the ages of 39 and 94. We examined them for their need for eye glasses as well as the prevalence of eye disease.
What we found was not very different from what has been found in other countries – 1 in 7 people examined were found to have some form of vision loss. Seventy per cent of those had uncorrected refractive error, which means that their vision loss could be corrected with a pair of eye glasses or contact lenses.
Furthermore, about one third of people screened showed signs of eye disease (cataracts, glaucoma, macular degeneration, diabetic retinopathy and a number of other eye conditions). Many of these people may not have known that they had eye disease. In fact, many eye diseases do not have any symptoms in the early stages.
In our study we asked people when they had last had their eyes examined. We found that about half the study population had not had their eyes examined in the past two years or more. What was even more telling was our finding that participants who had a longer time lapse since their last eye exam were more likely to have some level of vision loss.
Our study argues strongly for the need for regular eye exams. Many people may not even know that they have lost vision that can be corrected. Also, many people are likely unaware that they have eye disease. Early diagnosis and treatment of eye disease can lead to better outcomes and often minimize the amount of vision loss. But regular eye exams by an eye doctor are essential. Regular eye exams can also make sure that you get fitted with spectacles or contact lenses that will enable you to see better, and will make sure that you're not that person driving their car with vision that is less than optimal.