Table 1.

Frequency domain of HRV in subjects with primary hypertension and in the control group.

	Primary Hypertension	Control	P
	Awake state
LF	38.12 ± 1.05	33.79 ± 1.42	0.031
HF	34.63 ± 1.26	37.71 ± 1.12	0.018
LF/HF	1.28 ± 0.05	0.91 ± 0.04	0.002
	Sleep
LF	35.52 ± 1.17	32.69 ± 0.90	NS
HF	48.17 ± 1.98	54.57 ± 0.75	0.004
LF/HF	0.78 ± 0.06	0.60 ± 0.02	0.014

Values are means ± SE; LF - spectral power in low frequency band and HF - spectral power in high frequency band in normalized units (NU).