title: Differences in walking pattern during 6-min walk test between patients with COPD and healthy subjects.
abstract: BACKGROUND
  To date, detailed analyses of walking patterns using accelerometers during the 6-min walk test (6MWT) have not been performed in patients with chronic obstructive pulmonary disease (COPD). Therefore, it remains unclear whether and to what extent COPD patients have an altered walking pattern during the 6MWT compared to healthy elderly subjects.
  
  
  RESULTS
  79 COPD patients and 24 healthy elderly subjects performed the 6MWT wearing an accelerometer attached to the trunk. The accelerometer features (walking intensity, cadence, and walking variability) and subject characteristics were assessed and compared between groups. Moreover, associations were sought with 6-min walk distance (6MWD) using multiple ordinary least squares (OLS) regression models. COPD patients walked with a significantly lower walking intensity, lower cadence and increased walking variability compared to healthy subjects. Walking intensity and height were the only two significant determinants of 6MWD in healthy subjects, explaining 85% of the variance in 6MWD. In COPD patients also age, cadence, walking variability measures and their interactions were included were significant determinants of 6MWD (total variance in 6MWD explained: 88%).
  
  
  CONCLUSIONS
  COPD patients have an altered walking pattern during 6MWT compared to healthy subjects. These differences in walking pattern partially explain the lower 6MWD in patients with COPD.
authors.affiliation: Human Movement Science, NUTRIM School for Nutrition, Toxicology and Metabolism Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Janneke
authors.initials: J
authors.lastname: Annegarn
authors.forename: Martijn A
authors.initials: MA
authors.lastname: Spruit
authors.forename: Hans H C M
authors.initials: HH
authors.lastname: Savelberg
authors.forename: Paul J B
authors.initials: PJ
authors.lastname: Willems
authors.forename: Coby
authors.initials: C
authors.lastname: van de Bool
authors.forename: Annemie M W J
authors.initials: AM
authors.lastname: Schols
authors.forename: Emiel F M
authors.initials: EF
authors.lastname: Wouters
authors.forename: Kenneth
authors.initials: K
authors.lastname: Meijer
mesh_terms: D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D005684:Gait / Q000502:physiology*; D006801:Humans; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D013997:Time Factors; D016138:Walking / Q000502:physiology*