The optimal cut-off value for the one-minute sit-to-stand test to determine functional impairment in patients with pulmonary hypertension

Abstract Introduction Pulmonary hypertension (PH) often leads to reduced functional capacity, commonly assessed by the six-minute walk test (6MWT). The 1-min sit-to-stand test (1-min STST) is a shorter test with smaller space requirements. Despite its potential utility, to our knowledge no studies have determined the optimal cut-off value for the 1-min STST in patients with PH. Aim This study aimed to assess the optimal cut-off value for the 1-min STST by utilizing three established 6MWT thresholds (165m, 320m, and 440m) recommended in current European PH guidelines published by Humbert et al. (1). Methods A receiver operating characteristics (ROC) curve analysis was conducted to identify a threshold for the 1-min STST, aligning with the three 6MWT cut-offs. Clinical parameters and health-related quality of life (HRQoL) assessed through the Cambridge Pulmonary Hypertension Outcome Review (CAMPHOR) questionnaire were evaluated. Results A total number of 114 patients with PH (mean age 66±14 years, 57% female) were included in the analysis. Patients performed a mean number of 17±7 repetitions in the 1-min STST and achieved a mean 6MWT distance of 351±137m. The <165m 6MWT threshold revealed the highest area under the curve (AUC=0.90; 95%-CI 0.84-0.97). The optimal cut-off for the 1-min STST was 14.5 repetitions, exhibiting 69% sensitivity and 100% specificity. Patients below this threshold demonstrated significantly worse clinical parameters and reported worse HRQoL (p<0.001), as shown in Table 1. Conclusion A 1-min STST cut-off of 14.5 repetitions identified PH patients with functional impairment, suggesting its potential utility for risk stratification.