Baruch Vainshelboim1, Jonathan Myers, Jose Oliveira, Shimon Izhakian, Avraham Unterman, Mordechai Reuven Kramer. 1. Master of Cancer Care Program, School of Health Sciences, Saint Francis University, Loretto, Pennsylvania (Dr Vainshelboim); Pulmonary Institute, Rabin Medical Center, Beilinson Hospital, Petach Tikva, Israel (Drs Vainshelboim, Izhakian, Unterman, and Kramer); Research Center in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sport, University of Porto, Portugal (Drs Vainshelboim and Oliveira); Cardiology Division, Veterans Affairs Palo Alto Health Care System/Stanford University, California (Dr Myers); Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel (Drs Izhakian, Unterman, and Kramer).
Abstract
PURPOSE: This pilot study aimed to compare physiological responses between cycle cardiopulmonary exercise tests (CPETs) and 6-min walk tests (6MWTs) and to assess their prognostic value among patients with idiopathic pulmonary fibrosis (IPF). METHODS: Thirty-four patients with IPF (68 ± 8 yr) underwent CPETs and 6MWTs and were followed up for 40 mo. Differences, levels of agreement, and relative risks for mortality were analyzed between measured and estimated peak responses for the 2 tests. RESULTS: Compared with the CPET, oxygen uptake ((Equation is included in full-text article.)O2), heart rate (HR), and the nadir of SpO2 were lower during the 6MWT, whereas work rate (WR) was higher. Mean differences were as follows: (Equation is included in full-text article.)O2 =-1.9 mL/kg/min, 95% CI, -1.1 to -2.7, P < .001; HR =-9 beats/min, 95% CI, -4 to -14, P = .002; SpO2 =-6%, 95% CI, -4 to -7, P < .001; and WR = 9 W/min, 95% CI, 3 to 16, P = .008. Interclass correlations ranged from 0.84 to 0.90 and both tests demonstrated prognostic value for mortality. CONCLUSIONS: Significant differences and variation in peak physiological responses were observed between cycle CPETs and 6MWTs in patients with IPF. However, good agreement was evident, suggesting that both tests provide value for clinical and research settings. Future studies should compare the physiological responses between treadmill CPETs and 6MWTs for prognostic utility in IPF.
PURPOSE: This pilot study aimed to compare physiological responses between cycle cardiopulmonary exercise tests (CPETs) and 6-min walk tests (6MWTs) and to assess their prognostic value among patients with idiopathic pulmonary fibrosis (IPF). METHODS: Thirty-four patients with IPF (68 ± 8 yr) underwent CPETs and 6MWTs and were followed up for 40 mo. Differences, levels of agreement, and relative risks for mortality were analyzed between measured and estimated peak responses for the 2 tests. RESULTS: Compared with the CPET, oxygen uptake ((Equation is included in full-text article.)O2), heart rate (HR), and the nadir of SpO2 were lower during the 6MWT, whereas work rate (WR) was higher. Mean differences were as follows: (Equation is included in full-text article.)O2 =-1.9 mL/kg/min, 95% CI, -1.1 to -2.7, P < .001; HR =-9 beats/min, 95% CI, -4 to -14, P = .002; SpO2 =-6%, 95% CI, -4 to -7, P < .001; and WR = 9 W/min, 95% CI, 3 to 16, P = .008. Interclass correlations ranged from 0.84 to 0.90 and both tests demonstrated prognostic value for mortality. CONCLUSIONS: Significant differences and variation in peak physiological responses were observed between cycle CPETs and 6MWTs in patients with IPF. However, good agreement was evident, suggesting that both tests provide value for clinical and research settings. Future studies should compare the physiological responses between treadmill CPETs and 6MWTs for prognostic utility in IPF.
Authors: Owen Tomlinson; Anna Duckworth; Laura Markham; Rebecca Wollerton; Bridget Knight; Alexander Spiers; Michael Gibbons; Craig Williams; Chris Scotton Journal: BMJ Open Respir Res Date: 2021-04