Article

The test-retest reliability for multiple cardiopulmonary exercise
test (CPX) variables has not been compared in a single study and the influence of
different diseases on test-retest reliability has not been examined. We
investigated different measures of test-retest reliability for multiple variables
and compared them by category of cardiac or respiratory disease. METHODS: Patients with chronic obstructive airways disease (n = 24), heart failure (n =
43), or severe mitral valve disease (n = 26) were recruited into a prospective
study. Each patient underwent two bicycle ergometer tests; the first, a
familiarization test, with a 10 W/min ramp, and the second a personalized ramp
based on the results of the familiarization test to elicit maximal effort within
8-10 min. Intraclass correlation coefficients (ICC) and coefficients of variation
between the two tests were calculated. Influence of potential modifiers was
assessed using repeated measures analysis of variance. RESULTS: Peak VO2 (ICC
0.95, 95% CI 0.94-0.97), oxygen uptake efficiency slope (ICC 0.93, 95% CI
0.90-0.95), O2 pulse (ICC 0.96, 95% CI 0.94-0.97), and the VE/VCO2 ratio at the
nadir (ICC 0.92, 95% CI 0.89-0.95) all showed excellent test-retest reliability,
with within-subject coefficients of variation <0.12. VO2 at the anaerobic
threshold (ICC 0.84, 95% CI 0.78-0.89) and the VE/VCO2 slope (ICC 0.88, 95% CI
0.79-0.93) showed good test-retest reliability, although inferior to peak VO2.
Age, gender, body mass index, disease aetiology, protocol change, and intertest
interval did not affect the reliability of most variables. CONCLUSIONS: CPX
showed high test-retest reliability; certain variables such as peak VO2 and
oxygen uptake efficiency slope outperform others. These results identify which
variables are most suitable for serial testing of patients with three common
disease aetiologies owing to their superior reproducibility.

Langue : ANGLAIS