Table 3 Autonomic measures obtained from controls and non-apneic snorers during wakefulness and non-rapid eye movement sleep

NREM sleep

(without CPAP)

(Trial 1)

NREM sleep

(with CPAP)

(Trial 2)

NREM sleep

(without CPAP)

(snoring)

(Trial 1)

NREM sleep

(without CPAP)

(non-snoring)

(Trial 1)

NREM sleep

(with CPAP)

(Trial 2)

Heart rate (beats/min)

55.25 ± 1.53

54.58 ± 1.90

57.27 ± 1.45

55.18 ± 1.77

56.27 ± 1.74

Breathing Frequency (breaths/min)

14.89 ± 0.53

14.35 ± 0.46

13.85 ± 0.69

13.91 ± 0.53

14.23 ± 0.62

ln LF

7.24 ± 0.16

7.11 ± 0.13

7.68 ± 0.16

7.99 ± 0.27

7.41 ± 0.19

ln HF

7.99 ± 0.21

7.72 ± 0.19

8.19 ± 0.13

7.83 ± 0.18^§

7.40 ± 0.21^§

LF/HF

0.57 ± 0.12

0.70 ± 0.14

0.69 ± 0.08

1.43 ± 0.29^§

1.20 ± 0.18*

HF (nu)

67.51 ± 3.60

64.44 ± 3.95

62.46 ± 2.60

46.71 ± 5.38^§

50.32 ± 4.18*

LF (nu)

34.27 ± 4.37

39.24 ± 5.01

36.61 ± 2.58

52.0 ± 5.26^§

48.79 ± 4.09*