Functional capacity testing in patients with pulmonary hypertension (PH) using the one-minute sit-to-stand test (1-min STST).

Background: The one-minute sit-to-stand-test (1-min STST) is a quick, space saving test to evaluate functional capacity. Exercise testing plays an important role in the long-term follow-up of pulmonary hypertension (PH) patients and is currently evaluated using the six-minute-walk-test (6MWT). The aim of the study was to assess the convergent validity of the 1-min STST in patients with PH and its association with markers of PH severity.
Methods: We evaluated 106 PH patients with the 1-min-STST and 6MWT and measured cardiorespiratory parameters (heart rate, blood pressure, oxygen saturation) before and after test conduction. N-terminal pro brain-type natriuretic peptide (NT-proBNP), WHO functional class (WHO-FC) and mean pulmonary artery pressure (mPAP) were defined as markers of PH severity.
Results: Strong correlation was found between performances of 1-min STST and 6MWT (r = .711, p < .001), indicating convergent validity. Both tests were inversely associated with NT-proBNP (STST: r = -.405, p < .001; 6MWT: r = -.358, p < .001), WHO-FC (STST: r = -.591, p < .001; 6MWT: r = -.643, p < .001) and mPAP (STST: r = -.280, p < .001; 6MWT: r = -.250, p < .001). Significant changes in cardiorespiratory parameters were observed in both tests (all p < 0.001). Further the post-exercise cardiorespiratory parameters correlated strongly between the 1-min STST and 6MWT (all r ≥ .651, all p < .001).
Conclusion: The 1-min STST demonstrated good convergent validity with the 6MWT and was associated with markers of PH severity. Furthermore, both exercise tests caused similar cardiorespiratory responses.
Competing Interests: The authors have declared that no competing interests exist.
(Copyright: © 2023 Kronberger et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)