Background: In patients with COPD and isolated night time hypoxemia, oxygen administration has not shown any effects on life expectancy and the development of pulmonal arterial hypertension. The aim of the present pilot study was to investigate the influence of nocturnal oxygen therapy on the quality of life in daytime normoxemic COPD patients with nocturnal oxygen desaturations.
Patients and methods: 19 patients with COPD, in a stable phase of the disease without need for oxygen supplementation under rest (PaO2 62.7 +/- 4.9 mmHg) and nocturnal hypoxemia (t90 = 55.5 +/- 33.4 % of registration time, mean SaO2 89.8 +/- 1.9 %, minimal SaO2 81.1 +/- 4.8 %) were randomly assigned to either oxygen or placebo treatment, both generated by identical concentrator devices. Each treatment period lasted 6 weeks, after six weeks a cross-over was performed by a technician. Quality of life was assessed before and at the end of each treatment period by the SF-36, Nottingham Health Profile and Saint George's Respiratory Questionnaire.
Results: Significant differences for the comparison of placebo and verum were only seen for the dimension sleep (NHP), all other dimensions showed no differences between placebo and oxygen. However, both placebo and oxygen improved the majority of the quality of life items significantly.
Conclusions: The prescription of supplemental oxygen in COPD patients with isolated nocturnal hypoxemia in the present pilot study is not able to improve the quality of life within 6 weeks after initiation of therapy. It cannot, therefore, be generally recommended, but may be indicated in patients with a documented improvement of sleep quality.