New findings from researchers at the University of Michigan suggest a link between vision impairment in people over 71 and the risk of developing dementia. Published in JAMA Ophthalmology, the study underscores a potential connection between how clearly older adults see and their cognitive health as they age.
In a detailed analysis, researchers drew on data from nearly 3,000 Americans over the age of 71 who took part in the National Health and Aging Trends Study. The team evaluated both near and distance vision, along with the ability to discern objects against varied backgrounds. Tests were administered on tablets, and the researchers confirmed that, when the tests are conducted properly, tablet-based assessments can provide results that are comparable to conventional in-clinic eye examinations.
The results showed that even modest declines in vision were associated with a higher likelihood of dementia compared with those without vision problems. Overall, dementia symptoms were present in about 12.3 percent of participants. Among those with refractive errors, dementia was detected in 19.5 percent of individuals with myopia and in 21.5 percent of those with signs of farsightedness. Strikingly, dementia occurred in 32.9 percent of participants who had moderate to severe visual impairment, including clear losses of sight.
Beyond vision, dementia is shaped by a broader set of risk factors. Up to 40 percent of dementia cases may be linked to twelve modifiable factors, such as smoking, high blood pressure, and hearing loss. The study’s authors note that adding vision impairment to this list could influence future prevention efforts. If subsequent research confirms a causal relationship, aging adults who proactively manage vision health might lower their overall risk of dementia over time.
The research contributes to a growing body of evidence that sensory health is intertwined with cognitive health. Screenings that can be performed at home or in simple clinical settings, using portable devices, may offer practical opportunities to identify those at higher risk earlier. In turn, this could support timely interventions focused on both visual and cognitive well-being for older adults across North America, including Canada and the United States.
Historically, scientists have explored how perceptual changes reflect brain health. Early investigators examined how attention to visual detail might reveal underlying neural changes that precede more obvious cognitive symptoms. While the exact mechanisms remain under study, the new Michigan findings provide a compelling prompt for doctors, caregivers, and policymakers to consider sensory health as part of comprehensive dementia risk assessments.