Authors (including presenting author) :
WONG TY (1), Tam OY (1), TUNG LH(1), KWAN WS(1), MAK MY(1)
Affiliation :
(1) Department of Physiotherapy, Tuen Mun Hospital, New Territories West Cluster, Hospital Authority, Hong Kong
Keyword 2: :
Risk stratification
Keyword 3: :
Peri-operative management
Introduction :
Perioperative risk stratification is essential to identify patients at risk of adverse outcomes to reduce morbidity. The 30-second sit-to-stand test (30s STS) is a safe, feasible, and reliable telehealth tool for assessing lower limb strength, physical function, and frailty. Previous studies indicate that 30s STS predicts postoperative complications in lung resection surgery and that < 12.5 repetitions identify an anaerobic threshold < 11 ml/kg/min on cardiopulmonary exercise testing. However, no studies in Hong Kong have examined the relationship between 30s STS and the 6-Minute Walk Test (6MWT) or established a 30s STS cut-off for perioperative risk estimation.
Objectives :
1.To determine the correlation between STS and 6MWT 2.To determine the cut-off point for STS to stratify patients into “high risk” (6MWT < 400m) or “low risk” group (6MWT >= 400m)
Methodology :
This cross-sectional study was conducted at the Pre-Anesthetic Clinic of Tuen Mun Hospital from December 2024 to December 2025. All patients referred for lung resection surgery were recruited and completed the 6MWT (distance in meters) and 30s STS (repetitions). Data normality was assessed using the Shapiro-Wilk test. Pearson's correlation coefficient evaluated the association between 6MWT distance and 30s STS performance. Receiver operating characteristic (ROC) curve analysis determined the 30s STS cut-off for predicting ≥400 m on 6MWT to enable risk stratification.
Result & Outcome :
During the study period, 252 patients (126 males, 126 females) referred for lung resection surgery were recruited. Of these, 49 failed to achieve ≥400 m on the 6MWT and were classified as high-risk, while 203 achieved ≥400 m and were low-risk. Two patients did not complete the 6MWT (missing data). A moderate positive correlation was observed between 30-second sit-to-stand test (30s STS) repetitions and 6MWT distance (r=0.442, p< 0.001). Receiver operating characteristic (ROC) analysis showed good discriminative performance (AUC=0.797). A cut-off of < 8.5 repetitions on 30s STS provided 90% specificity and 15.2% sensitivity for identifying the high-risk group. The 30s STS is a quick, useful functional screening tool for predicting 6MWT distance. Our study showed that patients performing fewer than 8.5 repetitions in 30s STS are likely to walk < 400 m on 6MWT, classifying them as high-risk. As a safe and feasible test deliverable via telehealth, 30s STS provides a practical tool for remote perioperative risk stratification when in-person assessments are unavailable, such as for patients in remote areas with limited hospital access, or when logistical constraints prevent attendance at the preoperative clinic
