PURPOSE: To assess the validity, reliability, and sensitivity of a new self-administered physical activity questionnaire estimating daily energy expenditure (DEE) in patients with congestive heart failure (CHF). There is a need to develop a low cost, practical, and accurate tool increasing the knowledge of the type and dose of physical activity in patients with CHF for clinical and epidemiological aims.
METHODS: One hundred five participants with stable CHF performed an incremental symptom-limited VO2(peak) test and completed the questionnaire. For DEE calculation, time spent in each activity was multiplied by its energy cost corrected for weight, age, sex, autonomy, and the total was calculated over 24 h. Reproducibility and sensitivity of the questionnaire as well as interrater reliability were tested. Concurrent validity was assessed against VO2(peak), anthropometric characteristics and data from the literature.
RESULTS: Test-retest correlation coefficients used to measure reproducibility ranged from 0.82 for activities ranging from 3 to 5 METs to 0.98 for DEE and a paired Student's t-test didn't reach statistical significance for any activity score studied. Interrater reliability was high with an error in DEE estimation of 1.37% (t value = -1.064; P = NS). Sensitivity (changes in VO2(peak) concurrent to changes in DEE) was high (r = 0.88, P < 0.0001). DEE was in line with the literature in patients with CHF and relationships between DEE and VO2(peak) (r = 0.71, P < 0.0001), and DEE and anthropometric characteristics (<0.0001) were significant. Activity level above 3 METs was the best intensity criteria related to VO2(peak) (r = 0.62, P < 0.0001) and DEE (r = 0.80, P < 0.0001).
CONCLUSION: The questionnaire seems reliable, sensitive and valid for the estimation of DEE. VO2(peak) appears related to global DEE and more particularly to activities above 3 METs in patients with CHF.