Twelve-minute walking test in a group of Dutch patients with chronic obstructive pulmonary diseases; relationship...

Limitations in exercise tolerance are characteristic for patients with chronic obstructive pulmonary disease. The twelve-minute walking test has been proposed as a simple, reproducible test to assess exercise tolerance in these patients. We investigated factors, that predicted the twelve-minute walking distance in a group of fifty patients with COPD, who had a maximal reversibility in the FEV1 of 20% after inhaled salbutamol. There was a strong correlation between walking distance and IVC (%pred) (p less than 0.001), RV% TLC (%pred) (p less than 0.001), FEV1 (ml) (p less than 0.001), FEV1 (%pred) (p less than 0.001) and PaO2 (mm Hg) (p less than 0.01). It is concluded that pathophysiological factors are the main determinants of the twelve-minute walking distance.