Abstract
Purpose :
Visual impairment has been demonstrated to be associated with cognitive decline in older adults. However, the relationship between visual impairment and the severity of dementia is poorly understood.
Methods :
10,146 Participants aged 65 years and older from the National Alzheimer's Coordinating Center’s uniform data with baseline in-person visits from 2015 to 2021 were included. The mean age was 73.8 (SD 6.2) years (57% female, 14.0% Black, 9.3% Hispanic). Severity of dementia was measured by the Clinical Dementia Rating Scale Sum of Boxes (CDR-SOB) (mean score 1.9, SD 3.2, range 0-18, data skewed). Of the participants, 44.6% were cognitively normal (mean CDR-SOB 0.12), 30.5% had mild cognitive impairment (mean CDR-SOB 1.28), and 24.9% had dementia (mean CDR-SOB 5.95). During the visit, clinician judged visual function with and without corrective eyewear. Vision status was categorized into normal vision (92.3%), impaired vision (4.7%), and unknown vision (2.9%). Analysis of variance and negative binomial regression with CDR-SOB as outcome and vision status as predictor of interest were conducted to estimate the associations.
Results :
In subjects with dementia, those with impaired vision and those with unknown vision had higher CDR-SOB scores compared to normal vision (mean 5.67, 6.67 and 8.32 for normal vision, impaired vision, and unknown vision respectively, P<0.01). In a negative binomial regression of the entire sample, after adjusting for age, gender, race, Hispanic ethnicity, education, cognitive function, number of APOE e4 alleles, and the number of medications, impaired vision and unknown vision were associated with higher CDR-SOB scores compared to normal vision (Incidence rate ratio (IRR) 1.26, 95% CI [1.11, 1.44], p < 0.001 for impaired vision, and IRR 1.27, 95% CI [1.06, 1.53], P=0.01 for unknown vision) indicating worse dementia severity.
Conclusions :
In this large US multicenter Alzheimer’s Disease research center population, clinician judged visual impairment was associated with greater CDR-SOB adjusting for numerous covariates. Increased CDR-SOB scores are indicative of greater cognitive and functional impairment and more severe dementia staging. Persons with impaired vision or unknown vision are more likely to have advanced dementia staging. Clinician awareness of this association may be helpful for patient care.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.