Beschreibung:
AbstractBackgroundThe prevalence of frailty in asymptomatic Alzheimer’s disease is not clear. In this cohort screened for a preclinical Alzheimer’s disease clinical trial, we aimed to compare the prevalence of frailty between participants with and without elevated amyloid as determined by PET and determine if frailty influences the relationship between amyloid and cognition.MethodAnalysis of pre‐randomization data from the Anti‐Amyloid Treatment in Asymptomatic Alzheimer’s (A4) Study, a clinical prevention trial of an anti‐amyloid monoclonal antibody in individuals who were cognitively normal with elevated amyloid burden, to determine a cumulative‐deficits Frailty Index (FI). Logistic regression was used to investigate the difference in the prevalence of frailty, defined as a FI greater than 0.25, according to amyloid status (Aβ+/‐), adjusted for age, gender and education. ANCOVA was used to examine the influence of frailty on the relationship between amyloid status and cognition (Preclinical Alzheimer Cognitive Composite [PACC] score), including an interaction term of frailty and amyloid, adjusted for age, gender and education.Result4,486 participants were included (mean age 71.3±4.7 years, 1323 participants Aβ+(29.5%), 59.4% female). Adjusting for age, sex and education, Aβ+ participants were 1.48 times more likely to be frail compared to Aβ− (p<0.001). Frail participants had a lower PACC score compared to non‐frail participants (p<0.001). Both frailty and amyloid status were associated with poorer cognition after adjusting for age, sex and education (p<0.001), but frailty did not influence the relationship between cognition and amyloid status.ConclusionThere is strong evidence that elevated amyloid burden was associated with an increased risk of frailty and that frailty reduced cognitive performance compared to non‐frail participants in this cohort screened for a preclinical AD trial. These relationships, the potential underlying mechanisms, and whether this may be applicable to longitudinal outcomes, warrant further study.