Objective:
To determine whether impaired visual acuity is associated with dementia and cognitive dysfunction in older adults.
Design:Paired case-control comparisons of the relative frequencies of visual impairment in demented cases and nondemented controls.
Cohort analyses of correlation between visual acuity and cognitive functioning in demented cases.
Setting:Internal medicine clinics at two academically affiliated medical centers.
Participants:Eighty-seven consecutively selected patients ≥65 years of age with mild-to-moderate, clinically diagnosed Alzheimer’s disease
(cases) and 87 nondemented controls matched to the cases by age, sex, and education.
Measurements and main results:The prevalence of visual impairment was higher in cases than in controls [unadjusted odds ratio for near-vision impairment
=2.7 (95% CI=1.4, 5.2); unadjusted odds ratio for far-vision impairment =2.1 (95% CI=1.02, 4.3); odds ratios adjusted for
family history of dementia, depression, number of medications, and hearing loss were 2.5 (95% CI=1.1, 10.5) for near-vision
impairment and 1.9 (95% CI=0.8, 4.6) for far-vision impairment]. When further stratified by quartiles of visual acuity, no
statistically significant “dose-response” relationship between vision impairment and dementia risk was observed. Among cases,
the degree of visual impairment was significantly correlated with the severity of cognitive dysfunction for both near and
far vision (adjusted ps<0.001).
Conclusions:Visual impairment is associated with both an increased risk and an increased clinical severity of Alzheimer’s disease, but
the increased risk may not be consistent with a progressive dose-response relationship. Further studies are needed to determine
whether visual impairment unmasks and exacerbates the symptoms of dementia or is a marker of disease severity.
Key words dementia - Alzheimer’s disease - cognition - vision disorders - hearing disorders - aged
Supported by the Robert Wood Johnson Foundation Research and Development Program to Improve Patient Functional Status, the
University of Washington Alzheimer’s Disease Research Center (National Institutes of Health grant No. AG 05136) and Alzheimer’s
Disease Patient Registry (National Institutes of Health grant No. AG 06781), and National Institute on Aging Academic Award
No. K08 AG00265 (Dr. Uhlmann). The views expressed here are not necessarily those of the Robert Wood Johnson Foundation.