Cognitive Frailty and Adverse Health Outcomes: Findings From the Singapore Longitudinal Ageing Studies (SLAS)

Abstract

ObjectivesThere is a recent consensus proposal of “cognitive frailty” defined by the presence of both physical frailty and cognitive impairment in the absence of dementia. The relevance, validity, and utilization of cognitive frailty, however, is presently unclear. We determine whether concurrent physical frailty and cognitive impairment, compared with physical frailty alone substantially increased adverse health outcomes (functional disability, hospitalization, poor quality of life [QOL], and mortality). DesignLongitudinal study. SettingPopulation-based cohort (Singapore Longitudinal Ageing Study, SLAS). ParticipantsTwo thousand three hundred seventy-five Chinese Singaporeans aged 55 and above without dementia and degenerative disorders. MeasurementsThe associations of physical frailty (Cardiovascular Health Study criteria: 0 = robust, 1-2 = pre-frail, 3-5 = frail) with and without cognitive impairment (mini-mental state examination <26) and adverse outcomes were estimated, controlling for age, gender, education, comorbidity, smoking, alcohol consumption, depressive symptoms, baseline activities of daily living-instrumental and basic activities of daily living disability or QOL score. ResultsCompared to robust noncognitively impaired individuals, physical pre-frailty with cognitive impairment was associated with a twofold increased prevalence and incidence of functional disability, a twofold increased incidence of poor QOL, and 1.8-fold increased mortality risks. Cognitively impaired frail individuals stood out with 12- to 13-fold increased prevalence and incidence of functional disability, a five- and 27-fold increased prevalence and incidence of low QOL, and a fivefold increased mortality risk. The estimated prevalence of physical frailty with cognitive impairment was 1.8%, and physical pre-frailty with cognitive impairment was 8.9%. ConclusionPre-frailty and frailty with impaired cognitive function, found in 10.7% of this dementia-free population, was associated with an evidently high risk of adverse health outcomes.