Summary population attributable fraction of dementia prevalence associated with sensory risk factors

Abstract

Background

Hearing and vision loss can be treatable sensory risk factors for dementia. Nationally-representative estimates of the proportion of dementia prevalence associated with sensory risk factors in late-life are needed for dementia prevention strategies.

Objective

To estimate the fraction of dementia prevalence associated with treatable sensory risk factors (hearing and vision loss) and to evaluate differences by age, race/ethnicity, income, and sex.

Methods

This was a cross-sectional analysis of Round 12 (2022) of the National Health and Aging Trends Study, a population-based study nationally representative of US Medicare beneficiaries. Among community-living adults aged ≥65 years eligible for cognitive, hearing, and vision assessments (n = 4623), the summary population attributable fraction (PAF) of dementia from at least one objectively-measured sensory risk factor was estimated.

Results

The prevalence of at least one sensory risk factor was 66% and dementia was 9%. The PAF of dementia from at least one sensory risk factor was 57% (95% CI: 8%–61%). PAFs were larger for individuals who were aged <80 years compared to ≥80 years (59% [95% CI: 42%–74%] versus 33% [95% CI: −6%–68%), non-Hispanic White compared to Hispanic and non-Hispanic Black (63% [95% CI: 41%–80%] versus 50% [95% CI: 16%–80%] and 32% [95% CI: −1%–64%]), and had higher income versus lower income (57% [95% CI: 36%–74%] versus 47% [95% CI: 7%–81%]). PAFs were consistent by sex.

Conclusions

Up to 57% of dementia prevalence in the US was associated with clinically-significant sensory risk factors. Addressing sensory impairments could play an important role in national dementia risk reduction strategies.