Epidemiology of visuospatial impairment in older adults: the Harmonized Cognitive Assessment Protocol.

BACKGROUND AND OBJECTIVES: This study aimed to determine the prevalence of visuospatial impairment in a nationally representative sample of older adults and identify self- and informant-reported functional measures associated with visuospatial dysfunction.

METHODS: We analyzed data from 3496 participants aged ≥65 years in the 2016 Harmonized Cognitive Assessment Protocol (HCAP), a sub-study of the Health and Retirement Study. Visuospatial function was assessed using the Consortium to Establish a Registry for Alzheimer's Disease constructional praxis and Mini Mental State Examination pentagon copy tasks. Impairment was defined as a factor score >1.5 SDs below expected relative to a robust normative sample. Cognitive status was classified by HCAP as normal, mild cognitive impairment (MCI), or dementia. Logistic regression models examined associations between visuospatial impairment and functional outcomes, adjusting for demographic, health, and general cognitive factors.

RESULTS: Visuospatial impairment was present in 435 participants (11.33%). Among these, 49.85% had MCI, and 39.97% had dementia. Over half of those with MCI and visuospatial impairment had no other cognitive domain affected. Visuospatial impairment was associated with increased odds of self-reported visual difficulty (OR 1.60, 95% CI: 1.20-2.15), difficulty using a map (OR 3.35, 95% CI: 2.35-4.80), and informant-reported navigation difficulties, including getting lost at home (OR 17.30, 95% CI: 8.02-37.31). Associations with driving, map use, and getting lost at home remained significant after adjusting for general cognition.

DISCUSSION AND IMPLICATIONS: Visuospatial impairment is common among older adults, frequently occurs in isolation in MCI, and is strongly associated with functional limitations, particularly in navigation and driving.