Predictors of exercise capacity and everyday activity in older heart failure patients.
BACKGROUND
Exercise capacity and daily activity are key outcomes for older, frail heart failure patients. Little is known about the determinants of these outcomes in this patient group.


OBJECTIVE
To explore predictors of exercise capacity and daily activity in older, frail heart failure patients.


METHODS
Analysis of prospectively collected data from a cohort of 82 patients aged 70 years and over, enrolled in a randomised controlled trial of exercise in heart failure patients. Pathophysiological, demographic, psychological and social factors were analysed by multivariate regression to determine predictors of exercise capacity (6-min walk distance) and daily activity (daily accelerometer counts).


RESULTS
Between 49% and 55% of the variance in 6-min walk distance was explained by variables including New York Heart Association class, depression score, attitude to ageing and use of walking aids. Only 11% to 26% of the variance in accelerometer scores was explained by the model; 6-min walk distance was the only consistent predictor of daily activity.


CONCLUSIONS
Physical, psychological and attitudinal variables contribute to variance of the 6-min walk. Six-minute walk distance predicts a small amount of the variance in daily activity, but the majority of variance in daily activity remains unexplained and requires further investigation.
Witham
Miles D
MD
Section of Ageing and Health, University of Dundee, Ninewells Hospital, Dundee DD1 9SY, UK. m.witham@dundee.ac.uk
Argo
Ishbel S
IS
Johnston
Derek W
DW
Struthers
Allan D
AD
McMurdo
Marion E T
ME
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D015331:Cohort Studies; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006801:Humans; D008297:Male; D011446:Prospective Studies