REPRODUCIBILITY AND RESPONSIVENESS OF QUALITY-OF-LIFE ASSESSMENT AND 6-MINUTE WALK TEST IN ELDERLY HEART-FAILURE PATIENTS

Objective-To examine the reproducibility and responsiveness to change of a six minute walk test and a quality of life measure in elderly pat ients with heart failure. Design-Longitudinal within patient study. Su bjects-60 patients with heart failure (mean age 82 years) attending a geriatric outpatient clinic, 45 of whom underwent a repeat assessment three to eight weeks later. Main outcome measures-Subjects underwent a standardised six minute walk test and completed the chronic heart fai lure questionnaire (CHQ), a heart failure specific quality of life que stionnaire. Intraclass correlation coefficients (ICC) were calculated using a random effects one way analysis of variance as a measure of re producibility. Guyatt's responsiveness coefficient and effect sizes we re calculated as measures of responsiveness to change. Results-24 pati ents reported no major change in cardiac status, while seven had deter iorated and 14 had improved between the two clinic visits. Reproducibi lity was satisfactory (ICC > 0.75) for the six minute walk test, for t he total CHQ score, and for the dyspnoea, fatigue, and emotion domains of the CHQ. Effect sizes for all measures were large (> 0.8), and res ponsiveness coefficients were very satisfactory (> 0.7). Effect sizes for detecting deterioration were greater than those for detecting impr ovement. Conclusions-Quality of life assessment and a six minute walk test are reproducible and responsive measures of cardiac status in fra il, very elderly patients with heart failure.