title: [Six-minute walk work is not correlated to the degree of airflow obstruction in patients with Chronic Obstructive Pulmonary Disease (COPD)].
abstract: BACKGROUND
  The six-minute walking test distance, despite being considered the main parameter, does not consider body weight which is known to influence exercise capacity. A body of evidence shows the degree of airflow obstruction does not correlate to walking distance and the body weight affects the work/energy required to perform the walk.
  
  
  OBJECTIVE
  To verify if the degree of airflow obstruction correlates to six-minute walk work obtained by weight-walking distance product.
  
  
  METHODS
  A total of 60 patients with chronic obstructive pulmonary disease were evaluated. The physiological and functional variables were correlated to distance and body weight walking distance product (WxW).
  
  
  RESULTS
  There were no correlations between six- minute walk work and the degree of airflow obstruction. A positive and significant correlation were observed between the distance and Carbon Monoxide Diffusing Capacity (DLCO) (r=0.6; p<0.01) and between the distance and final SatO 2 (r= 0.3 ; p <0.05). Correlation between distance and Borg scale was negative and significant (r= -0.3; p<0.05). The six-minute walk work was positive and significantly correlated to DLCO (r= 0.7; p<0.01) and negative but significantly correlated to Borg scale in the initial (r= - 0.3; p<0.01) and final of the test (r= -0.4; p<0.05).
  
  
  CONCLUSIONS
  Based on this data, there was no correlation between the degree of airflow obstruction and six-minute walk work test. The DLCO was the only respiratory functional parameter significantly correlated to the distance and to the six- minute walk work.
authors.affiliation: Centro Universitário Feevale of Novo Hamburgo, and Pulmonology Sciences Post Graduate Programme, Universidade Federal do Rio Grande do Sul, CEP 93352-000 Novo Hamburgo, RS, Brazil. paulojzt@feevale.br
authors.forename: Paulo José Zimermann
authors.initials: PJ
authors.lastname: Teixeira
authors.forename: Cássia Cínara
authors.initials: CC
authors.lastname: Costa
authors.forename: Danilo Cortozi
authors.initials: DC
authors.lastname: Berton
authors.forename: Greice
authors.initials: G
authors.lastname: Versa
authors.forename: Otávio
authors.initials: O
authors.lastname: Bertoletti
authors.forename: Dáversom Bordin
authors.initials: DB
authors.lastname: Canterle
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology*; D012123:Pulmonary Ventilation; D013997:Time Factors; D016138:Walking / Q000502:physiology*