Heart Rate Variability in Patients with Hypertension: the Effect of Metabolic Syndrome and Antihypertensive Treatment

Table 2

Comparison of HRV parameters in subgroups stratified by concomitant MetS (before treatment initiation).

	MetS [+],	MetS [-],	value
SDNN_24h [ms]	135.5	149.1	0.048
SDNN_day [ms]	109.8	121.5	0.015
SDNN_night [ms]	90.5	94.6	0.473
rMSSD_24h [ms]	31.5	38.2	0.002
rMSSD_day [ms]	27.3	32.7	0.002
rMSSD_night [ms]	40.0	49.0	0.020
pNN50_24h [%]	6.80	10.79	0.0008
pNN50_day [%]	4.66	7.63	0.0004
pNN50_night [%]	12.65	19.28	0.018
LF/HF_day [-]	4.50	3.88	0.625
LF/HF_night [-]	3.04	2.01	0.048
LF_day [n.u.]	70.5	70.0	0.939
LF_night [n.u.]	62.3	55.8	0.061
HF_day [n.u.]	23.0	24.1	0.524
HF_night [n.u.]	32.3	38.3	0.041
TP_day [ms^2]	2.747	3.248	0.152
TP_night [ms^2]	2.923	3.174	0.616

DBP: diastolic blood pressure; HF: power in the high frequency range; HR: heart rate; LF: power in the low frequency range; n.u. : normalized units; pNN50: percentage of NN50; rMSSD: square root of the mean of the sum of the squares of differences between adjacent NN intervals; SBP: systolic blood pressure; SDNN: standard deviation of the average of NN intervals; TP: total power of variance of all NN intervals.