The reproducibility and sensitivity of the 6-min walk test in elderly patients with chronic heart failure

Ingle, Lee; Shelton, Rhidian J.; Rigby, Alan S.; Nabb, Samantha; Clark, Andrew L.; Cleland, John G.F.

Abstract

Aims: The 6-min walk test (6-MWT) is used to estimate functional capacity. However, in elderly patients with chronic heart failure (CHF): (i) 1 year reproducibility of the 6-MWT; (ii) sensitivity of the 6-MWT to self-perceived changes in symptoms of heart failure; and (iii) implications for patient numbers required for studies using the 6-MWT as an endpoint have not been described. Methods and results: One thousand and seventy-seven patients with CHF, aged > 60, with NYHA Class ≥II were recruited. Heart failure symptom assessment was determined using a questionnaire related to aspects of physical function, and patients performed a baseline 6-MWT, with follow-up 1 year later. Seventy-four patients with unchanged symptoms had an unchanged 6-MWT distance, with an overall intraclass correlation coefficient of 0.80 (95% CI = 0.69-0.87). Four hundred and twenty-three patients reported an improvement in symptoms during follow-up. There was a negative correlation (r = -0.55; P = 0.0001) between Δ symptoms and Δ 6-MWT (i.e. a reduced 6-MWT distance is associated with reduced symptom severity at follow-up). Five hundred and sixteen patients reported worsening symptoms of heart failure, a moderate inverse correlation (r = -0.53; P = 0.0001) was displayed between Δ symptoms and Δ 6-MWT. For all patients, irrespective of symptom status, a high inverse correlation (r = -0.75; P = 0.0001) was evident. On the basis of the data for patients with unchanged symptoms, it is calculated that to detect an increase in 6-MWT of 50 m, with 90% power, a study size of approximately 120 is required. Conclusion: In elderly patients with CHF, the 6-MWT shows satisfactory agreement when repeated 1 year later. Change in 6-MWT distance is sensitive to change in self-perceived symptoms of heart failure. © The European Society of Cardiology 2005. All rights reserved.

Citation

Ingle, L., Shelton, R. J., Rigby, A. S., Nabb, S., Clark, A. L., & Cleland, J. G. (2005). The reproducibility and sensitivity of the 6-min walk test in elderly patients with chronic heart failure. European Heart Journal, 26(17), 1742-1751. https://doi.org/10.1093/eurheartj/ehi259

• Journal Article Type: Article
• Acceptance Date: Mar 15, 2005
• Online Publication Date: Apr 14, 2005
• Publication Date: 2005-09
• Deposit Date: May 7, 2019
• Journal: European Heart Journal
• Print ISSN: 0195-668X
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 26
• Issue: 17
• Pages: 1742-1751
• DOI: https://doi.org/10.1093/eurheartj/ehi259
• Keywords: Symptoms of heart failure; Elderly patients; 1 year follow-up; Power curves
• Public URL: https://hull-repository.worktribe.com/output/738489
• Publisher URL: https://academic.oup.com/eurheartj/article/26/17/1742/428518