The construct validity of the Steep Ramp Test for assessing cardiorespiratory fitness in patients with breast cancer, and the impact of chemotherapy-related symptom burden.

Van de Wiel HJ; Groen WG; Kampshoff CS; Buffart LM; van Mechelen W; van Harten WH; Aaronson PDNK;
Stuiver PDMM;

Archives of physical medicine and rehabilitation [Arch Phys Med Rehabil] 2022 Jun 19.
Date of Electronic Publication: 2022 Jun 19.

Objective: To investigate the construct validity of the Steep Ramp Test by longitudinally comparing the correlation between Maximum Short Exercise Capacity (MSEC) of the Steep Ramp Test (SRT) and direct measurements of VO 2 peak during or shortly after treatment in patients with breast cancer and the potential impact of chemotherapy-induced symptom burden.
Design: Cross-sectional SETTING: Multicenter PARTICIPANTS: We used data from two studies that included women with breast cancer treated with chemotherapy, resulting in 274 observations. 161 patients performed the Cardiopulmonary Exercise Test (CPET) and the Steep Ramp Test in two test sessions on different time points around chemotherapy treatment.
Interventions: Not Applicable MAIN OUTCOME MEASURES: Fatigue was assessed with the Multidimensional Fatigue Inventory, and nausea and vomiting and pain by the EORTC Quality of Life Questionnaire -Core 30. The longitudinal correlation between the Maximum Short Exercise Capacity and VO 2 peak was investigated using a linear mixed model. Interaction terms were added to the model, to investigate whether the correlation varied by symptom burden.
Results: We found a statistically significant moderate correlation between VO₂peak and Maximum Short Exercise Capacity (.61, 95% CI; .51 .70, p < .01) over time. This correlation was slightly attenuated (-.07, 95% CI; -.13 .00, p = .04) in patients’ with chemotherapy-related nausea and vomiting, indicating smaller correlations of VO 2 peak with the Maximum Short Exercise Capacity with increasing symptom burden. Pain and fatigue did not significantly modify the correlation.
Conclusion: The Steep Ramp Test can only be used as a proxy for changes in aerobic capacity with great caution and with attention for the level of nausea and vomiting.