Continuous Oxygen Use Linked to Increased Mortality
Poorer outcomes associated with continuous oxygen use among non-hypoxic COPD patients
TUESDAY, Sept. 9 (HealthDay News) -- Continuous oxygen use in non-hypoxic patients with severe emphysema is common and identifies a high-risk cohort of emphysema patients, researchers report in the September issue of Chest.
Michael B. Drummond, M.D., of the Johns Hopkins University School of Medicine in Baltimore, and colleagues studied patients in the National Emphysema Treatment Trial and compared chronic obstructive pulmonary disease (COPD) outcomes in non-hypoxic patients treated with continuous oxygen and non-hypoxic patients not using oxygen.
Of the 1,215 patients analyzed, 260 non-hypoxic patients reported continuous oxygen use and 226 non-hypoxic patients were not using oxygen, the researchers report. In unadjusted analyses, continuous oxygen use without hypoxemia was associated with more dyspnea, poorer quality of life, more common exercise desaturation, and a higher case-fatality rate, the investigators found. In adjusted analyses, the more frequent exercise desaturations accounted for the majority increased case-fatality rate indicating that the increase in deaths may not be due to oxygen therapy but rather a marker for more severe disease.
"The main finding in this exploratory study is that use of oxygen in normoxic patients identifies a high-risk group of emphysema patients," the authors write. "Normoxic participants using continuous oxygen demonstrated more frequent exercise desaturation, lower spirometric values, poorer exercise performance, more dyspnea and worse survival."