PAP (mm Hg) | Mean(SD) difference | 95% CI | p value | ||
---|---|---|---|---|---|
Patients were breathing oxygen during the first period of sleep and air during the second period. Normal controls were breathing air throughout. Exercise refers to steady state exercise on the cycle ergometer at 30 watts. | |||||
COPD group | |||||
Asleep breathing air | 59.8 (8.1) | ||||
Asleep breathing oxygen | 50.8 (5.5) | Asleep breathing oxygen v asleep breathing air | 9.6 (5.3) | (4.9 to 14.3) | 0.016 |
Exercise | 59.0 (10.7) | Exercise v asleep breathing air | 0.8 (8.9) | (–7.0 to 8.6) | 0.851 |
Normal group | |||||
Asleep breathing air | 14.6 (5.9) | ||||
Asleep breathing oxygen | 14.6 (7.0) | Asleep breathing oxygen v asleep breathing air | 0.0 (2.4) | (–2.1 to 2.1) | 1.000 |
Exercise | 17.0 (4.0) | Exercise v asleep breathing air | 3.3 (2.2) | (1.1 to 5.5) | 0.061 |