Cognitive impairment improves the predictive validity of the phenotype of frailty for adverse health outcomes: the three-city study.
OBJECTIVE
To determine whether adding cognitive impairment to frailty improves its predictive validity for adverse health outcomes.


METHODS
Four-year longitudinal study.


METHODS
The French Three-City Study.


METHODS
Six thousand thirty community-dwelling persons aged 65 to 95.


METHODS
Frailty was defined as having at least three of the following criteria: weight loss, weakness, exhaustion, slowness, and low physical activity. Subjects meeting one or two criteria were prefrail and those meeting none as nonfrail. The lowest quartile in the Mini-Mental State Examination (MMSE) and the Isaacs Set Test (IST) was used to identify subjects with cognitive impairment. The predictive validity of frailty for incident disability, hospitalization, dementia, and death was calculated first for frailty subgroups and then rerun after stratification according to the presence or absence of cognitive impairment.


RESULTS
Four hundred twenty-one individuals (7%) met frailty criteria. Cognitive impairment was present in 10%, 12%, and 22% of the nonfrail, prefrail, and frail subjects, respectively. Those classified as frail scored lower on the MMSE and IST than those classified as prefrail and nonfrail. After adjustment, frail persons with cognitive impairment were significantly more likely to develop disability in activities of daily living (ADLs) and instrumental ADLs over the following 4 years. The risk of incident mobility disability and hospitalization was marginally greater. Incident dementia was greater in the groups with cognitive impairment irrespective of their frailty status. Conversely, frailty was not a significant predictor of mortality.


CONCLUSIONS
Cognitive impairment improves the predictive validity of the operational definition of frailty, because it increases the risk of adverse health outcomes in this particular subgroup of the elderly population.
Avila-Funes
José Alberto
JA
Centre de Recherche Inserm, U897, Bordeaux, France.
Amieva
Hélène
H
Barberger-Gateau
Pascale
P
Le Goff
Mélanie
M
Raoux
Nadine
N
Ritchie
Karen
K
Carrière
Isabelle
I
Tavernier
Béatrice
B
Tzourio
Christophe
C
Gutiérrez-Robledo
Luis Miguel
LM
Dartigues
Jean-François
JF
D000203:Activities of Daily Living / Q000145:classification; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D003072:Cognition Disorders / Q000175:diagnosis / Q000401:mortality*; D015897:Comorbidity; D015140:Dementia, Vascular / Q000175:diagnosis / Q000401:mortality*; D005260:Female; D016330:Frail Elderly / Q000706:statistics & numerical data*; D005602:France; D015577:Geriatric Assessment / Q000706:statistics & numerical data*; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D008609:Mental Status Schedule / Q000706:statistics & numerical data; D051346:Mobility Limitation; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D010641:Phenotype; D011594:Psychometrics / Q000706:statistics & numerical data; D012307:Risk Factors; D012959:Socioeconomic Factors; D015431:Weight Loss