Using the 6-minute walk test to predict disability-free survival after major surgery.

Journal Article (Journal Article;Multicenter Study)

BACKGROUND: The 6-min walk test (6MWT) is a common means of functional assessment. Its relationship to disability-free survival (DFS) is uncertain. METHODS: This sub-study of the Measurement of Exercise Tolerance for Surgery study had co-primary outcome measures: correlation of the preoperative 6MWT distance with 30 day quality of recovery (15-item quality of recovery) and 12 month WHO Disability Assessment Schedule scores. The prognostic utility of the 6MWT and other risk assessment tools for 12 month DFS was assessed with logistic regression and receiver-operating-characteristic-curve analysis. RESULTS: Of 574 patients recruited, 567 (99%) completed the 6MWT. Twelve months after surgery, 16 (2.9%) patients had died and 444 (77%) had DFS. The 6MWT correlated weakly with 30 day 15-item quality of recovery (ρ=0.14; P=0.001) and 12 month WHO Disability Assessment Schedule (ρ=-0.23; P<0.0005) scores. When the cohort was split into 6MWT distance tertiles, the adjusted odds ratio of low vs high tertiles for DFS was 3.13 [95% confidence interval (CI): 1.54-6.35]. The only independent variable predictive of DFS was the Duke Activity Status Index (DASI) score (adjusted odds ratio: 1.06; P<0.0005). The area under the receiver-operating-characteristic curve for DFS was 0.63 (95% CI: 0.57-0.70) for the 6MWT, 0.60 (95% CI: 0.53-0.67) for cardiopulmonary-exercise-testing-derived peak oxygen consumption, and 0.70 (95% CI: 0.64-0.76) for the DASI score. CONCLUSIONS: Of the risk assessment tools analysed, the DASI was the most predictive of DFS. The 6MWT was safe and comparable with cardiopulmonary exercise testing for all predictive assessments. Future research should aim to determine the optimal 6MWT distance thresholds for risk prediction.

Full Text

Duke Authors

Cited Authors

  • Shulman, MA; Cuthbertson, BH; Wijeysundera, DN; Pearse, RM; Thompson, B; Torres, E; Ambosta, A; Wallace, S; Farrington, C; Myles, PS; Measurement of Exercise Tolerance for Surgery Study Investigators,

Published Date

  • January 2019

Published In

Volume / Issue

  • 122 / 1

Start / End Page

  • 111 - 119

PubMed ID

  • 30579389

Electronic International Standard Serial Number (EISSN)

  • 1471-6771

Digital Object Identifier (DOI)

  • 10.1016/j.bja.2018.08.016


  • eng

Conference Location

  • England