Assessing Risk for Adverse Outcomes in Older Adults: The Need to Include Both Physical Frailty and Cognition

Abstract

BACKGROUND: Physical frailty is a powerful tool for identifying nondisabled individuals at high-risk of adverse outcomes. The extension to which cognitive impairment in those without dementia adds value to physical frailty in detecting high-risk individuals remains unclear. OBJECTIVES: To estimate the effects of combining physical frailty and cognitive impairment without dementia (CIND) on the risk of basic activities of daily living (ADL) dependence and death over eight years. DESIGN: Prospective cohort study. SETTING: The Health and Retirement Study (HRS). PARTICIPANTS: 7,338 community-dwelling people aged ≥65 years without dementia and ADL dependence at baseline (2006–2008). Follow-up assessments occurred every 2 years until 2014. MEASUREMENTS: The five components of the Cardiovascular Health Study defined physical frailty. A well-validated HRS method, including verbal recall, series of subtractions, and backward count task, assessed cognition. Primary outcomes were time to ADL dependence and death. Hazard models, considering death as competing risk, associated physical frailty and CIND with outcomes after adjusting for sociodemographics, comorbidities, depression and smoking status. RESULTS: The prevalence of physical frailty was 15%; CIND, 19%; and both deficits, 5%. In unadjusted and adjusted analyses, combining these factors identified older adults at an escalating risk for ADL dependence (no-deficit=14% [reference group]; only-CIND=26%, sub-hazard ratio [sHR]=1.5, 95% confidence interval [CI]=1.3–1.8; only-frail=33%, sHR=1.7, 95%CI 1.4–2.0; both-deficits=46%, sHR=2.0, 95%CI=1.6–2.6) and death (no-deficit=21%; only-CIND=41%, HR=1.6, 95%CI=1.4–1.9; only-frail=56%, HR=2.2, 95%CI=1.7–2.7; both-deficits=66%, HR=2.6, 95%CI=2.0–3.3) over eight-year follow-up. Adding the cognitive measure to models that already included physical frailty alone increased accuracy in identifying those at higher risk of ADL dependence (Harrell’s C 0.74 vs 0.71; P<0.001) and death (Harrell’s C 0.70 vs 0.67; P<0.001). CONCLUSION: Physical frailty and CIND are independent predictors of incident disability and death. Since together physical frailty and CIND identify vulnerable older adults better, risk assessment among older adults should include both physical and cognitive elements.

Association between cognitive impairment and criteria for frailty syndrome among older adults

“…Both frailty and cognitive impairment are risk factors for future adverse outcomes, such as dementia, disability, hospitalization and death. These outcomes have been confirmed in Brazilian and non-Brazilian older adults 42, 43,44,45 .…”

Clinical and Neuropsychological Correlates of Prefrailty Syndrome

“…Cross-sectional and longitudinal research has demonstrated that older adults with physical frailty exhibit poorer cognitive performance and greater risk of cognitive decline and dementia than individuals without frailty (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15), and that individuals with cognitive decline or dementia show a higher risk of physical frailty (16)(17)(18). It has also been demonstrated that the coexistence of physical frailty and cognitive impairment (cognitive frailty), ranging from 1 to 5% in community-dwelling older adults (19), increases the risk of mortality (20)(21)(22)(23)(24)(25), functional disability (26), and incident neurocognitive disorders (9,27) in later life. Importantly, the rates of change of frailty and cognition over time are strongly correlated and associated with the same brain pathologies, such as the presence of macroinfarcts, Alzheimer's disease pathology, and nigral neuronal loss (28).…”

Longitudinal Relationship Between Frailty and Cognition in Patients 50 Years and Older with Breast Cancer

“…Additionally, a greater annual rate of change in frailty is associated with a subsequent development of Alzheimer's disease . Physical function and cognitive impairment were shown to be independent predictors of incident disability and death in older adults without cancer, and when cognitive measures are added to frailty assessment, the combination was better at identifying vulnerable older adults at risk of future activities of daily living dependence …”

“…12 Physical function and cognitive impairment were shown to be independent predictors of incident disability and death in older adults without cancer, and when cognitive measures are added to frailty assessment, the combination was better at identifying vulnerable older adults at risk of future activities of daily living dependence. 13 Given our aging population, the prevalence of cancer, and the association of cognitive impairment with frailty in older adults, improved understanding of the relationships between frailty and cognition in cancer is critical for managing these risk factors. [14][15][16][17] This analysis evaluates frailty and its relation to cognition longitudinally over the course of adjuvant chemotherapy and up to 6 months postchemotherapy, in patients with breast cancer aged 50 years and older, including both subjective and objective assessments of cognition.…”