Instrumental activities of daily living, amyloid, and cognition in cognitively normal older adults screening for the A4 Study

Abstract

Introduction: We examined the associations among instrumental activities of daily living (IADL), cortical amyloid, and cognition in cognitively normal (CN) older adults. Methods: CN participants screening for the A4 Study (n = 4486) underwent florbetapir (amyloid) positron emission tomography. IADL were assessed using the Alzheimer's Disease Cooperative Study Activities of Daily Living Prevention Instrument. Separate logistic regression models were run with cortical amyloid or cognition as independent variable and IADL as dependent variable, adjusting for age and sex. Results: IADL difficulties were endorsed infrequently (≤16%). Overall IADL and four select IADL item difficulties (“remembering appointments,” “finding belongings,” “following TV programs,” and “remembering current events”) reported by both participant and study partner were significantly associated with greater amyloid burden and worse cognition. Discussion: Although IADL deficits were infrequent in this CN cohort, greater participant and study partner report of overall IADL deficits and subtle difficulties in specific IADL items were associated with mildly higher amyloid burden and worse cognition.