Ambulatory oximetry fails to predict survival in chronic obstructive pulmonary disease with mild-to-moderate hypoxaemia.

Background And Objective: Although long-term oxygen therapy is one of few treatments known to improve survival in COPD, no patient subgroup likely to derive benefit has been identified in over 30 years. We assessed the prognostic value of point measurement of P(a) O(2) and proportion of ambulatory oximetry with saturations below 90% in this context.

Methods: Subjects were community-living patients with COPD and P(a) O(2) 56-70 mm Hg when stable.