The utility and safety of one-minute sit-to-stand test in pulmonary hypertension: a prospective study

<bold>Introduction:</bold> Functional exercise capacity in patients with pulmonary hypertension (PH) is routinely assessed using the 6-minute walking test (6MWT). However, alternative tests should be useful because of resource requirements. This study aimed to evaluate whether the 1-minute sit-to-stand test (1STST) is useful and safe in patients with PH and whether it can replace the 6MWT. <bold>Methods:</bold> Adult patients with PH at our hospital were recruited from September 2023 to February 2024. The correlation between the number of 1STST repetitions (1STSTr) and 6-minute walk distance (6MWD), the relationship between the 1STSTr and pulmonary hemodynamic parameters and quadriceps muscle strength, adverse events and vital sign fluctuations during the tests, and a questionnaire with an 11-point Likert scale (−5, 6MWT favor; 5, 1STST favor) were evaluated. <bold>Results:</bold> Eighteen patients (PH group 1, n=9; PH group 4, n=9) were enrolled. The median age was 58 years (18-81). The WHO functional classification was as follows (I, 2; II, 13; III, 3). The 1STSTr and 6MWD were 24±8 and 430m±125m, respectively, with a strong correlation (<italic>r</italic>=0.767 [95%CI 0.467-0.908]). There was no significant correlation between the 1STSTr and pulmonary hemodynamic markers or quadriceps muscle strength. No serious adverse events or motor impairments occurred. The variability of SpO₂ during the tests was significantly lower in the 1STST (−5.1%±3.0% vs. -8.8%±12.2%). The questionnaire showed a predominant opinion in favor of 1STST (3.0±2.8). <bold>Conclusion:</bold> The 1STST is a reliable alternative to the 6MWT for measuring exercise capacity in patients with PH. Adopting 1STST can alleviate the burden on patients and medical staff.