TY - JOUR
T1 - The minimal important difference of the constant work rate cycle test in severe COPD
AU - van der Molen, Marieke C.
AU - Slebos, Dirk Jan
AU - Augustijn, Sonja W.S.
AU - Kerstjens, Huib A.M.
AU - Hartman, Jorine E.
N1 - Funding Information:
Lung Foundation Netherlands (grant number 5.1.17.171.0 ).
Publisher Copyright:
© 2023 The Authors
PY - 2023/8/1
Y1 - 2023/8/1
N2 - Background: The Constant Work Rate Cycle Test (CWRT) is a commonly used and sensitive test to detect treatment success in patients with Chronic Obstructive Pulmonary Disease (COPD). Earlier, the Minimal Important Difference (MID) of the CWRT was estimated at 101 s (or 34%) change from baseline based on one well executed study. However, this study was performed in a population of patients with mild-to-moderate COPD, and we have learned that MIDs might be quite different in patients with severe COPD. Therefore, we aimed to establish the MID of the CWRT in patients with severe COPD.Methods: We included 141 patients with severe COPD, who underwent either pulmonary rehabilitation, bronchoscopic lung volume reduction with endobronchial valves, or a sham bronchoscopy as a control group. CWRT workload was set at 75% of the peak work capacity, as determined by an incremental cycle test. We used the change in 6-min walking test (6-MWT), forced expiratory volume in 1s (FEV1), residual volume (RV), and St. George's Respiratory Questionnaire (SGRQ) total score as anchors to calculate the MID.Results: All anchors had an association of ≥0.41 with change in CWRT. The MID estimates for the different anchors were: 6-MWT 278 s (95%), FEV1 273 s (90%), RV 240 s (84%), and SGRQ 208 s (71%). The average of these four MID estimates resulted in an MID of 250 s (or 85%).Conclusion: We established the MID for CWRT at 250 s (or 85%) change from baseline in patients with severe COPD.
AB - Background: The Constant Work Rate Cycle Test (CWRT) is a commonly used and sensitive test to detect treatment success in patients with Chronic Obstructive Pulmonary Disease (COPD). Earlier, the Minimal Important Difference (MID) of the CWRT was estimated at 101 s (or 34%) change from baseline based on one well executed study. However, this study was performed in a population of patients with mild-to-moderate COPD, and we have learned that MIDs might be quite different in patients with severe COPD. Therefore, we aimed to establish the MID of the CWRT in patients with severe COPD.Methods: We included 141 patients with severe COPD, who underwent either pulmonary rehabilitation, bronchoscopic lung volume reduction with endobronchial valves, or a sham bronchoscopy as a control group. CWRT workload was set at 75% of the peak work capacity, as determined by an incremental cycle test. We used the change in 6-min walking test (6-MWT), forced expiratory volume in 1s (FEV1), residual volume (RV), and St. George's Respiratory Questionnaire (SGRQ) total score as anchors to calculate the MID.Results: All anchors had an association of ≥0.41 with change in CWRT. The MID estimates for the different anchors were: 6-MWT 278 s (95%), FEV1 273 s (90%), RV 240 s (84%), and SGRQ 208 s (71%). The average of these four MID estimates resulted in an MID of 250 s (or 85%).Conclusion: We established the MID for CWRT at 250 s (or 85%) change from baseline in patients with severe COPD.
U2 - 10.1016/j.rmed.2023.107265
DO - 10.1016/j.rmed.2023.107265
M3 - Article
C2 - 37224889
AN - SCOPUS:85159921730
SN - 0954-6111
VL - 215
JO - Respiratory Medicine
JF - Respiratory Medicine
M1 - 107265
ER -