Connection between heart rate variability alterations and cancer in tumor patients

Table 2 Results of the heart rate variability for cancer patients

Index	Reference group[7,8]	Cancer group	P value
Total		127
Time domain analysis, 24 hours
SDNN, ms	141 ± 39	102.12 ± 23.48	< 0.05
SDANN, ms	127 ± 35	95.3 ± 31.25	< 0.05
SDNNIDX, ms	50 ± 13	38.3 ± 21.4	< 0.05
Triangle index	37 ± 15	24.0 ± 5.12	< 0.05
pNN50, %	7.95 ± 8.15	4.06 ± 0.59	< 0.05
Frequency domain analysis, 24 hours			< 0.05
VLF, ms2	1124 ± 316	631.9 ± 275.3	< 0.05
LF, ms2	1170 ± 416	426 ± 153	< 0.05
LF/HF	1.75 ± 0.67	1.29 ± 0.48	< 0.05

SDNN: SD of the all normal-to-normal intervals; SDANN: SD of the average values of normal-to-normal intervals; SDNNIDX: mean of SD of normal-to-normal intervals for 5 minutes; pNN50: Percentage of normal-to-normal intervals differing from each other by > 50 ms; VLF: Very low frequency; LF: Low frequency; HF: High frequency.