One-minute sit-to-stand test cut-offs for risk stratification based on six-minute walk test thresholds in pulmonary hypertension.

AIMS

We aimed to establish one-minute sit-to-stand test (1-min STST) cut-off values that align with the guideline-recommended six-minute walk test (6MWT) thresholds (165m and 440m) for one-year mortality risk stratification in pulmonary hypertension (PH) patients. Furthermore, we aimed to compare clinical characteristics and long-term mortality among patients stratified by these proposed 1-min STST cut-offs.

METHODS

All patients performed the 1-min STST and 6MWT. Receiver operating characteristics analysis was performed to determine 1-min STST cut-offs corresponding to the 6MWT thresholds. Patients were stratified into three groups based on these cut-offs.

RESULTS

Among 114 PH patients (mean age 66±14 years, 57% female), the mean number of 1-min STST repetitions was 17±6 and the mean 6MWT distance was 354±133m. The aligning 1-min STST cut-off for the <165m 6MWT threshold was 14 repetitions (sensitivity 69%, specificity 100%) with an AUC of 0.90 (95%-CI 0.84-0.97). For the >440m threshold, 20 repetitions (sensitivity 81%, specificity 84%) aligned with an AUC of 0.85 (95%-CI 0.75-0.94). Patients performing ≤14 repetitions had worse NT-proBNP levels (p<0.001), WHO-FC (p<0.001), mPAP (p=0.050), as well as health-related quality of life (HRQoL) (p<0.001) and a higher rate of mortality than those performing ≥20 repetitions (p=0.020).

CONCLUSION

The 1-min STST cut-offs aligning with the 6MWT thresholds of 165m and 440m are 14 and 20 repetitions, respectively. Patients performing ≤14 repetitions demonstrated worse clinical parameters and higher mortality rates, making the 1-min STST a potential risk stratification tool in PH patients.