Cognitive Decline and Dementia May Be Proceeded By Vision Impairment

Cognitive decline and dementia are more likely in patients who have had vision impairment (VI), according to study findings published in the American Journal of Ophthalmology.

“Maintaining good vision and eye health may help preserve cognitive function in older age, though more research is needed to investigate the potential benefits of interventions that focus on vision and eye health on cognitive outcomes,” according to the researchers.

Researchers conducted a cross-sectional analysis to evaluate the association between visual impairment and the odds of cognitive decline and dementia. The study included 3206 participants (55% women; 82% white).

Weighted prevalence rates were 10% for distance VI, 22% for near VI, 22% for CSI, 34% for any objective VI, and 7% for self-reported VI. Dementia was more than twice as prevalent in adults with VI compared with their peers without dementia, across all measures of VI (P <.001 for all).

The study found that all measures of VI were associated with higher odds of dementia (distance VI – OR: 1.74 [95% CI: 1.24-2.44], near VI – OR: 1.68 [95% CI: 1.29-2.18], CSI – OR: 1.95 [95% CI: 1.45-2.62], any objective VI – OR: 1.83 [95% CI: 1.43-2.35], self-reported VI – OR: 1.86 [95% CI: 1.20-2.89]).

The researchers explain that, though there is an existing body of research supporting the association between VI and cognitive decline and dementia, the majority of studies have used self-report of visual function for assessment. Though self-report is useful information, the study noted, objective visual function measures may be more clinically valuable for healthcare professionals.

The study also highlights that, in addition to its primary finding of the association between cognitive decline and dementia and poor visual acuity and contrast sensitivity, the individual parameters of cognition were observed to be consistently impaired in those with VI, which further supports the study’s hypothesis.

“Moreover, adults with any measure of VI had worse cognitive performance across all cognitive domains (psychomotor function, visual attention, and working memory) compared to adults without impairment,” the researchers explain.

Study limitations include possible confounding of results due to the lack of formal clinical diagnosis for the diagnosis of dementia; and the possibility that study results are not generalizable outside of the Medicare beneficiary population.