Elderly people with visual disorders that are left untreated are significantly more likely to develop Alzheimer's disease -- the most common form of dementia, according to a University of Michigan Health System study.
The study used Medicare data and shows that those with poor vision who visited an ophthalmologist at least once for an examination were 64 percent less likely to develop dementia.
The study appears online ahead of print in the American Journal of Epidemiology and may draw a new picture of poor vision as predictor of dementia rather than as a symptom after the diagnosis.
"Visual problems can have serious consequences and are very common among the elderly, but many of them are not seeking treatment," says lead author Mary A.M. Rogers, Ph.D, research assistant professor of internal medicine at the U-M Medical School and research director of the Patient Safety Enhancement Program at the U-M Health System and the Ann Arbor VA Medical Center.
For the study, Rogers and her colleague Kenneth M. Langa, M.D., Ph.D., professor of internal medicine at U-M Medical School, analyzed data from the nationally representative Health and Retirement Study and records from Centers for Medicare and Medicaid Services.
"Our results indicate that it is important for elderly individuals with visual problems to seek medical attention so that the causes of the problems can be identified and treated," Rogers says.
The types of vision treatment that were helpful in lowering the risk of dementia were surgery to correct cataracts and treatments for glaucoma, retinal disorders and other eye-related problems.
Proper vision is a requirement for many of the activities that previously have been found to lower the risk of Alzheimer's disease. These include reading, playing board games, other mentally stimulating activities, social networking, as well as physical activity such as walking and routine exercising. A visual disorder may interfere with normal mobility and may also hinder a person's ability to participate in such activities.
"Many elderly Americans do not have adequate health coverage for vision, and Medicare does not cover preventative vision screenings for most beneficiaries," Rogers says. "So it's not unusual that the elderly receive vision treatment only after a problem is severe enough to warrant a visit to the doctor when the problem is more advanced."