How to Score the Peak Oxygen Consumption Obtained Through Cardiopulmonary Exercise Test in Individuals after Stroke?

Objectives: To compare five distinct methods to score the peak of oxygen consumption (VO2peak) obtained through the cardiopulmonary exercise testing (CPET) in individuals after stroke. Materials and methods: The VO2peak was obtained through the CPET with five methods: method-1: the highest value of the test; method-2: the highest value of the last 30 seconds at peak exercise; method-3: the mean of the last 30 seconds at peak exercise; method-4: the mean of the last 20 seconds at peak exercise; method-5: the highest value averaged of the 3 last blocks of 10 seconds at peak exercise. The coefficient of variance (CV) and the mean differences with 95% confidence interval (CI) between the scoring methods were calculated. A post-hoc test (Tukey HSD) was performed to calculate the adjusted 95%CI. Results: Fifty-nine individuals were included (54 +/- 12 years, 56 +/- 60 months after stroke). The CV of the methods 1-to-5 were, respectively: 27.91%, 25.77%, 23.38%, 23.83%, and 23.33%. There was no difference between method-1 and method-2 (95%CI: -1.10 to 4.69) and between methods 3 to 5: method-3 and method-4 (95%CI: -2.97 to 2.82); method-3 and method-5 (95%CI: -3.57 to 2.22); method-4 and method-5 (95%CI: -3.49 to 2.30). However, method-1 and -2 provided VO2peak values different from that of methods 3-to-5. Conclusions: The scoring method of obtaining the VO(2pea)k has an influence on its magnitude. Since methods 3-to-5 showed lower CV and provided similar values, they should be used to calculate the VO2peak obtained through the CPET in individuals after stroke.