From: Nocturnal CPAP improves walking capacity in COPD patients with obstructive sleep apnoea
Heart rate variability | Overlap syndrome n = 18# |  | COPD |  | ||
---|---|---|---|---|---|---|
n = 20@ | ||||||
 | Baseline | With CPAP | p | Baseline | With CPAP | p |
LF (nu) | 46.6 ± 16.1 | 31.3 ± 16.7 | 0.001 | 31.8 ± 10.8* | 28.7 ± 20.4 | 0.401 |
HF (nu) | 32.2 ± 12.0 | 43.1 ± 19.1 | 0.029 | 41.9 ± 12.1* | 43.6 ± 19.3 | 0.287 |
LF/HF | 1.8 ± 1.2 | 0.9 ± 0.7 | 0.003 | 0.9 ± 0.6* | 1.2 ± 1.9 | 0.514 |
Urine catecholamines | Overlap syndrome n = 12 $ |  | COPD |  | ||
n = 12 $ | ||||||
 | Baseline | With CPAP |  | Baseline | With CPAP |  |
Norepinephrine, ug | 17.0 ± 8.4 | 10.4 ± 6.4 | 0.003 | 11.1 ± 5.3* | 11.9 ± 7.5 | 0.485 |
Epinephrine, ug | 2.4 ± 0.9 | 1.4 ± 0.7 | 0.025 | 1.5 ± 0.6* | 1.8 ± 0.8 | 0.374 |