Renae J McNamara1, Sarah Houben-Wilke2, Frits M E Franssen3, Dionne E Smid4, Lowie E G W Vanfleteren5, Miriam T J Groenen6, Nicole H M K Uszko-Lencer7, Emiel F M Wouters8, Jennifer A Alison9, Martijn A Spruit10. 1. Department of Research and Education, CIRO, Horn, The Netherlands; Departments of Respiratory and Sleep Medicine and Physiotherapy, Prince of Wales Hospital, Randwick, Australia. Electronic address: renae.mcnamara@health.nsw.gov.au. 2. Department of Research and Education, CIRO, Horn, The Netherlands. Electronic address: sarahwilke@ciro-horn.nl. 3. Department of Research and Education, CIRO, Horn, The Netherlands. Electronic address: fritsfranssen@ciro-horn.nl. 4. Department of Research and Education, CIRO, Horn, The Netherlands. Electronic address: dionnesmid@ciro-horn.nl. 5. Department of Research and Education, CIRO, Horn, The Netherlands. Electronic address: lowievanfleteren@ciro-horn.nl. 6. Department of Research and Education, CIRO, Horn, The Netherlands. Electronic address: miriangroenen@ciro-horn.nl. 7. Department of Research and Education, CIRO, Horn, The Netherlands. Electronic address: nicolelencer@ciro-horn.nl. 8. Department of Research and Education, CIRO, Horn, The Netherlands; Department of Respiratory Medicine, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands. Electronic address: ewouters@ciro-horn.nl. 9. Discipline of Physiotherapy, The University of Sydney, Lidcombe, Australia. Electronic address: jennifer.alison@sydney.edu.au. 10. Department of Research and Education, CIRO, Horn, The Netherlands; Department of Respiratory Medicine, Maastricht University Medical Centre, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht, The Netherlands. Electronic address: martijnspruit@ciro-horn.nl.
Abstract
BACKGROUND: Exercise limitation in COPD is multi-factorial. The contribution of cardiac function to exercise capacity is not clear. METHODS: Potential determinants of the different constructs of exercise capacity (functional, peak and endurance exercise capacity using the 6-minute walk distance (6MWD), peak oxygen uptake (VO2peak) and peak work load, and sub-maximal constant work rate test (CWRT) cycle time, respectively) were analysed. RESULTS: Data were collected in 516 people with COPD (56% male, age (mean ± SD) 64 ± 9 years, FEV1% predicted 49 ± 20%). Participants had reduced exercise capacity (6MWD 424 ± 124 m, 67 ± 18% predicted; VO2peak 1090 ± 414 ml/min, 66 ± 30% predicted; peak work load 70 ± 34 watts, 56 ± 27% predicted; CWRT cycle time (median (IQR)) 225 (169-328) seconds). Cardiac function measures, including echocardiography and N-terminal pro-brain natriuretic peptide level, were independently significantly correlated with exercise capacity. In multiple regression analyses adjusted for age and gender, 72% (p < 0.001) of the 6MWD variance could be explained, with the timed up-and-go test accounting for 32% of the variance. For VO2peak, 60% (p < 0.001) of the variance could be explained, with FEV1 accounting for 30% of the variance. Quadriceps total work was a significant determinant of all exercise tests. CONCLUSIONS: Cardiac function is related to exercise capacity, however is not a primary determinant. Determinants of the different constructs of exercise capacity vary, but there is a strong relationship between quadriceps force and functional and endurance exercise performance, and between lung function and peak exercise capacity.
BACKGROUND: Exercise limitation in COPD is multi-factorial. The contribution of cardiac function to exercise capacity is not clear. METHODS: Potential determinants of the different constructs of exercise capacity (functional, peak and endurance exercise capacity using the 6-minute walk distance (6MWD), peak oxygen uptake (VO2peak) and peak work load, and sub-maximal constant work rate test (CWRT) cycle time, respectively) were analysed. RESULTS: Data were collected in 516 people with COPD (56% male, age (mean ± SD) 64 ± 9 years, FEV1% predicted 49 ± 20%). Participants had reduced exercise capacity (6MWD 424 ± 124 m, 67 ± 18% predicted; VO2peak 1090 ± 414 ml/min, 66 ± 30% predicted; peak work load 70 ± 34 watts, 56 ± 27% predicted; CWRT cycle time (median (IQR)) 225 (169-328) seconds). Cardiac function measures, including echocardiography and N-terminal pro-brain natriuretic peptide level, were independently significantly correlated with exercise capacity. In multiple regression analyses adjusted for age and gender, 72% (p < 0.001) of the 6MWD variance could be explained, with the timed up-and-go test accounting for 32% of the variance. For VO2peak, 60% (p < 0.001) of the variance could be explained, with FEV1 accounting for 30% of the variance. Quadriceps total work was a significant determinant of all exercise tests. CONCLUSIONS: Cardiac function is related to exercise capacity, however is not a primary determinant. Determinants of the different constructs of exercise capacity vary, but there is a strong relationship between quadriceps force and functional and endurance exercise performance, and between lung function and peak exercise capacity.
Authors: Erik Frykholm; Sarah Gephine; Didier Saey; Arthur Lemson; Peter Klijn; Eline Bij de Vaate; François Maltais; Hieronymus van Hees; André Nyberg Journal: Sci Rep Date: 2021-06-02 Impact factor: 4.379