The Cognitive-Prefrail Syndrome and Its Association With Adverse Health Outcomes: Results From the NuAge Observational Population-based Study

Scientific Summary

Background Cognitive frailty is the simultaneous presence of both physical frailty and cognitive impairment, excluding concurrent dementia. This condition confers a greater risk of incident cognitive impairment and decline, dementia, falls and disabilities compared to either condition alone. Current definitions of co-existent frailty and cognitive impairment exist, including the International Academy on Nutrition and Aging (IANA) and the International Association of Gerontology and Geriatrics (IAGG) consensus for cognitive frailty. There is also an analogous construct known as the motoric cognitive risk syndrome (MCR) associating slow gait speed and subjective cognitive impairment (SCI). Current operational criteria identify individuals later in the trajectory of frailty and cognitive decline, which may be too late for effective interventions. The researchers propose to define a new and early condition in the spectrum of Cognitive frailty known as "cognitive-prefrailty", which is a combination of prefrailty stage and SCI.

Overall objective This study aims to determine and compare (1) the prevalence of cognitive-prefrailty, cognitive frailty (IANA/IAGG consensus definition) and MCR syndromes, (2) the incidence and predictive ability of these three syndromes for adverse health outcomes including cognitive impairment and decline, dementia, physical functional impairment and decline, falls, hospitalization and mortality in older community dwellers.

Methods This study will use the database of the "Nutrition as a determinant of successful aging: The Quebec longitudinal study" (NuAge) study, which is a population-based observational cohort hat recruited healthy community-dwellers with age ranged from 67 to 84 years (51.8% women) between November 2003 and June 2005, and followed them during 4 years. Cognitive-prefrailty, prefrailty and MCR will be defined using information collected at the baseline assessment. Incident adverse health outcomes including cognitive impairment and decline, dementia, physical functional impairment and decline, falls, hospitalization and mortality have been recorded during the 4-years follow-up period.

Anticipated results Prefrailty (an intermediate and potentially reversible stage between robust and frailty) and SCI occur upstream in the continuum of frailty and cognitive decline and hence constitute more suitable targets for screening and early intervention in older adults.