Table 3. Heart rate variability parameters of the groups.

Data are expressed as mean±SD and median (interquartile range) as appropriate.

SDNN: standard deviation of R-R intervals; RMSSD: root mean square of successive differences; pNN50: proportion of NN50 divided by the total number of R-R intervals; LF: low frequency; HF: high frequency

Parameters	Study group, (n=90)	Control group, (n=70)	p-Value
SDNN (ms)	102.6±43.2	140.3±18.9	<0.001
RMSSD (ms)	32.6±22.5	28.7±8.9	0.558
pNN50 (%)	10.6±9.2	8.0±5.3	0.492
LF (nu)	67.6±15.6	53.8±12.4	<0.001
HF (nu)	27.2±11.2	25.2±7.6	0.446
LF/HF	3.54±1.8	2.24±1.3	0.003