Table 5.

Spectral parameters at baseline and after 24-h, 28-h, 32-h SD in normotensive, pre-hypertensive and hypertensive groups in resting conditions.

Parameter	Time	Group I mean ± SD	Group II mean ± SD	Group III mean ± SD	I vs. II p-value	I vs. III p-value	II vs. III p-value
LF-RRI	Baseline	1391.1 ± 838.5	1702.6 ± 2404.5	748.2 ± 846.5	ns	ns	ns
	24-h TSD	1314.6 ± 1208.0	1079.0 ± 840.0	798.6 ± 791.0	ns	ns	ns
	28-h TSD	1790.2 ± 1300.1	1341.6 ± 1178.7	1005.3 ± 1032.9	ns	ns	ns
	32-h TSD	1003.8 ± 810.0	1264.0 ± 1036.8	931.1 ± 1023.5	ns	ns	ns
HF-RRI	Baseline	1189.4 ± 786.9	1480.1 ± 2975.1	436.9 ± 514.5	ns	0.0418	ns
	24-h TSD	1111.5 ± 1148.7	1173.9 ± 1922.9	598.5 ± 560.8	ns	ns	ns
	28-h TSD	2761.8 ± 4638.3	1065.1 ± 1634.4	608.1 ± 643.9	ns	0.0183	ns
	32-h TSD	1039.3 ± 1016.8	1491.1 ± 266.6	796.9 ± 872.9	ns	ns	ns

Bolded values = values which are statistically significant, p < 0.05.