Evaluation of cardio-respiratory parameters during the stair climbing test and the six minutes walking test

Villiot-Danger, Estelle Villiot-Danger, Jean Christophe Reychler, Gregory [UCL] Razzouk, Hassan

Background: The stair climbing test (SCT) could be used as an alternative to the six minutes walking test (6MWT) to assess exercise tolerance in COPD patients. Objective: To compare the relationship between evolution of dyspnoea, oxygen saturation and heart rate during the stair climbing test and the 6MWT. Material and method: A self-paced 2-minutes SCT and a 6MWT were performed on a separate day in 36 stable COPD patients (Age = 65.1 ± 12.7 y.o.; FEV1 = 54 ± 17.5 % pred.val.; BMI = 25.3 ± 4.3kg.m-2) without encouragement. Arterial oxygen saturation (SpO2), heart rate (HR), and dyspnoea (VAS) were measured before, during and immediately after both tests. Climbed and walked distances were measured at the end of the tests. Results: Delta HR and maximum HR measured during exercise were significantly different for each test (38 ±17 bpm and 109 ±11 bpm vs 25 ±12 bpm and 104 ±16 bpm, p<0.001 and p=0.01 for SCT and 6MWT respectively). Difference between pre- and post-exercise saturation tended to be different between both tests (3 ±3% and 4 ±2% for SCT and 6MWT respectively, p=0.056). Difference between pre- and post-exercise dyspnoea was significantly greater with SCT than with 6MWT (6 ±2 vs 4 ±2, p<0.001). There was a significant correlation between FEV1 and climbed distance (r=0.44, p<0.01) and walked distance (r=0.34, p<0.05). Conclusion: These results highlight that HR and dyspnoea increase to a greater extent during the SCT compared to the 6MWT despite similar changes in SpO2.