Distance and Oxygen Desaturation During the 6-min Walk Test as Predictors of Long-term Mortality in Patients With COPD

Casanova C, Cote C, Marin JM, Pinto-Plata V, de Torres JP, Aguirre-Jaíme A, Vassaux C, Celli BR.


In this study 576 stable COPD outpatients in Spain and the United States were enrolled and observed them for at least 3 years. FEV1, body mass index, PaO2, Charlson comorbidity score, 6-min walk distance (6MWD), and oxygen saturation by pulse oximetry (SpO2) during the 6MWT. Regression analysis helped determine the association between these variables and all-cause and respiratory mortality.


The results showed that the 6MWD was a good predictor of all-cause and respiratory mortality primarily in patients with FEV1 < 50% of predicted. Patients with desaturation during the 6MWT had a higher mortality rate than patients without desaturation. Oxygen desaturation (drop of >4% or less than 90%) predicted mortality but with less power than PaO2 at rest.


Chest 2008; 134: 746 – 752


Link to Abstract