RATIONALE: The 6-minute-walk test (6MWT) is a practical and clinically meaningful measure of exercise tolerance with favorable performance characteristics in various cardiac and pulmonary diseases. Performance characteristics in patients with idiopathic pulmonary fibrosis (IPF) have not been systematically evaluated. OBJECTIVES: To assess the reliability, validity, and responsiveness of the 6MWT and estimate the minimal clinically important difference (MCID) in patients with IPF. METHODS: The study population included all subjects completing a 6MWT in a clinical trial evaluating interferon gamma-1b (n = 822). Six-minute walk distance (6MWD) and other parameters were measured at baseline and at 24-week intervals using a standardized protocol. Parametric and distribution-independent correlation coefficients were used to assess the strength of the relationships between 6MWD and measures of pulmonary function, dyspnea, and health-related quality of life. Both distribution-based and anchor-based methods were used to estimate the MCID. MEASUREMENTS AND MAIN RESULTS: Comparison of two proximal measures of 6MWD (mean interval, 24 d) demonstrated good reliability (coefficient = 0.83; P < 0.001). 6MWD was weakly correlated with measures of physiologic function and health-related quality of life; however, values were consistently and significantly lower for patients with the poorest functional status, suggesting good construct validity. Importantly, change in 6MWD was highly predictive of mortality; a 24-week decline of greater than 50 m was associated with a fourfold increase in risk of death at 1 year (hazard ratio, 4.27; 95% confidence interval, 2.57- 7.10; P < 0.001). The estimated MCID was 24-45 m. CONCLUSIONS: The 6MWT is a reliable, valid, and responsive measure of disease status and a valid endpoint for clinical trials in IPF.
RCT Entities:
RATIONALE: The 6-minute-walk test (6MWT) is a practical and clinically meaningful measure of exercise tolerance with favorable performance characteristics in various cardiac and pulmonary diseases. Performance characteristics in patients with idiopathic pulmonary fibrosis (IPF) have not been systematically evaluated. OBJECTIVES: To assess the reliability, validity, and responsiveness of the 6MWT and estimate the minimal clinically important difference (MCID) in patients with IPF. METHODS: The study population included all subjects completing a 6MWT in a clinical trial evaluating interferon gamma-1b (n = 822). Six-minute walk distance (6MWD) and other parameters were measured at baseline and at 24-week intervals using a standardized protocol. Parametric and distribution-independent correlation coefficients were used to assess the strength of the relationships between 6MWD and measures of pulmonary function, dyspnea, and health-related quality of life. Both distribution-based and anchor-based methods were used to estimate the MCID. MEASUREMENTS AND MAIN RESULTS: Comparison of two proximal measures of 6MWD (mean interval, 24 d) demonstrated good reliability (coefficient = 0.83; P < 0.001). 6MWD was weakly correlated with measures of physiologic function and health-related quality of life; however, values were consistently and significantly lower for patients with the poorest functional status, suggesting good construct validity. Importantly, change in 6MWD was highly predictive of mortality; a 24-week decline of greater than 50 m was associated with a fourfold increase in risk of death at 1 year (hazard ratio, 4.27; 95% confidence interval, 2.57- 7.10; P < 0.001). The estimated MCID was 24-45 m. CONCLUSIONS: The 6MWT is a reliable, valid, and responsive measure of disease status and a valid endpoint for clinical trials in IPF.
Authors: Souheil El-Chemaly; Angelo Taveira-Dasilva; Hilary J Goldberg; Elizabeth Peters; Mary Haughey; Don Bienfang; Amanda M Jones; Patricia Julien-Williams; Ye Cui; Julian A Villalba; Shefali Bagwe; Rie Maurer; Ivan O Rosas; Joel Moss; Elizabeth P Henske Journal: Chest Date: 2017-02-10 Impact factor: 9.410
Authors: John E Morley; Angela Marie Abbatecola; Josep M Argiles; Vickie Baracos; Juergen Bauer; Shalender Bhasin; Tommy Cederholm; Andrew J Stewart Coats; Steven R Cummings; William J Evans; Kenneth Fearon; Luigi Ferrucci; Roger A Fielding; Jack M Guralnik; Tamara B Harris; Akio Inui; Kamyar Kalantar-Zadeh; Bridget-Anne Kirwan; Giovanni Mantovani; Maurizio Muscaritoli; Anne B Newman; Filippo Rossi-Fanelli; Giuseppe M C Rosano; Ronenn Roubenoff; Morris Schambelan; Gerald H Sokol; Thomas W Storer; Bruno Vellas; Stephan von Haehling; Shing-Shing Yeh; Stefan D Anker Journal: J Am Med Dir Assoc Date: 2011-07 Impact factor: 4.669
Authors: Anthony W Castleberry; Brian R Englum; Laurie D Snyder; Mathias Worni; Asishana A Osho; Brian C Gulack; Scott M Palmer; R Duane Davis; Matthew G Hartwig Journal: Am J Respir Crit Care Med Date: 2015-10-01 Impact factor: 21.405
Authors: Cory L Christiansen; Thomas Fields; Guy Lev; Ryan O Stephenson; Jennifer E Stevens-Lapsley Journal: PM R Date: 2015-05-12 Impact factor: 2.298