Six-minute-walk test in chronic obstructive pulmonary disease: Minimal clinically important difference for death or hospitalization

Michael I. Polkey, Martijn A. Spruit, Lisa D. Edwards, Michael L. Watkins, Victor Pinto-Plata, Jørgen Vestbo, Peter M.A. Calverley, Ruth Tal-Singer, Alvar Agustí, Per S. Bakke, Harvey O. Coxson, David A. Lomas, William MacNee, Stephen Rennard, Edwin K. Silverman, Bruce E. Miller, Courtney Crim, Julie Yates, Emiel F.M. Wouters, Bartolome Celli

Research output: Contribution to journalArticlepeer-review

173 Scopus citations


Rationale: Outcomes other than spirometry are required to assess nonbronchodilator therapies for chronic obstructive pulmonary disease. Estimates of the minimal clinically important difference for the 6-minute-walk distance (6MWD) have been derived from narrow cohorts using nonblinded intervention. Objectives: To determine minimum clinically important difference for change in 6MWD over 1 year as a function of mortality and first hospitalization in an observational cohort of patients with COPD. Methods:Data fromtheECLIPSEcohortwereused(n=2,112).Death or first hospitalizationwere indexevents;wemeasured change in6MWDin the 12-month period before the event and related change in 6MWD to lungfunctionandSt. George'sRespiratoryQuestionnaire (healthstatus). Measurement and Main Results: Of subjects with change in the 6MWD data, 94 died, and 323 were hospitalized. 6MWD fell by 29.7 m (SD, 82.9 m) more among those who died than among survivors (P<0.001). A reduction in distance of more than 30 m conferred a hazard ratio of 1. 93(95%confidenceinterval, 1.29-2.90;P= 0.001) for death. No significant difference was observed for first hospitalization. Weak relationships only were observed with change in lung function or health status. Conclusions: A reduction in the 6MWD of 30 m or more is associated withincreased riskofdeath butnot hospitalizationdueto exacerbation in patientswith chronic obstructive pulmonary disease and represents a clinically significantminimally important difference.

Original languageEnglish (US)
Pages (from-to)382-386
Number of pages5
JournalAmerican Journal of Respiratory and Critical Care Medicine
Issue number4
StatePublished - Feb 15 2013


  • 6MW
  • COPD
  • Death
  • Hospitalization
  • MCID

ASJC Scopus subject areas

  • Pulmonary and Respiratory Medicine
  • Critical Care and Intensive Care Medicine

Fingerprint Dive into the research topics of 'Six-minute-walk test in chronic obstructive pulmonary disease: Minimal clinically important difference for death or hospitalization'. Together they form a unique fingerprint.

Cite this