The Association between Frailty and Dementia-Free and Physical Disability-Free Survival in Community-Dwelling Older Adults

Abstract

Introduction: Frailty is a common geriatric syndrome that adversely impacts health outcomes. This study examined correlates of physical frailty in healthy community-dwelling older adults and studied the effect of frailty on disability-free survival (DFS), defined as survival free of independence-limiting physical disability or dementia. Methods: This is a post hoc analysis of 19,114 community-dwelling older adults (median age: 74.0 years, interquartile range or IQR: 6.1 years) from Australia and the USA enrolled in the "ASPirin in Reducing Events in the Elderly (ASPREE)"clinical trial. Frailty was assessed using a modified Fried phenotype and a deficit accumulation frailty index (FI) utilizing a ratio score derived from 66 items. Multinomial logistic regression was used to examine the correlates of frailty and Cox regression to analyze the association between frailty and DFS (and its components). Results: At study enrollment, 39.0% were prefrail, and 2.2% of participants were frail, according to Fried phenotype. Older age, higher waist circumference, lower education, ethnoracial origin, current smoking, depression, and polypharmacy were associated with prefrailty and frailty according to Fried phenotype and FI. Fried phenotype defined prefrailty and frailty predicted reduced DFS (prefrail: HR: 1.67; 95% CI: 1.50-1.86 and frail: HR: 2.80; 95% CI: 2.27-3.46), affecting each component of DFS including dementia, physical disability, and mortality. Effect sizes were larger, according to FI. Conclusion: Our study showed that prefrailty is common in community-dwelling older adults initially free of cardiovascular disease, dementia, or independence-limiting physical disability. Prefrailty and frailty significantly reduced disability-free survival. Addressing modifiable correlates, like depression and polypharmacy, might reduce the adverse impact of frailty on dementia-free and physical disability-free survival.