Table 2.
Characteristics of heart rate variability variables, both absolute and log transformed values, of the study participants.
| HRV Variables | Absolute values Median (IQR) |
Log Transformed Mean ± SD/Median [IQR] |
|---|---|---|
| SDNN | 60.27 (47.56, 81.54) | 1.77 ± 0.16 |
| RMSSD | 46.22 (35.85, 85.96) | 1.70 ± 0.24 |
| pNN50 | 26.97 (12.99, 44.59) | 1.30 ± 0.47 |
| Total power | 3265.43 (2111.73, 7243.57) | 3.52 ± 0.35 |
| VLF (ms2) | 1085.41 (610.98, 1879.44) | 3.00 ± 0.37 |
| LF (ms2) | 1027.67 (560.64, 1707.54) | 2.96 ± 0.36 |
| HF (ms2) | 891.82 (453.53, 2879.03) | 3.00 ± 0.47 |
| LF/HF ratio | 0.90 (0.50, 1.55) | 0.04 (0.29,0.19) |
Abbreviations: Frequency domain variables of Heart rate variability: VLF- Absolute power of the very-low-frequency band (0.0033–0.04 Hz)– milli-second square, LF - Power in the low-frequency range (0·04–0·15 Hz), HF - Power in the high-frequency range (0·15–0·4 Hz), LF/HF ratio -Ratio of LF [ms2]/HF [ms2].
Time-domain variables of HRV: SDNN- Standard deviation of NN intervals(ms), RMSSD- Root mean square of successive RR interval differences(ms), pNN50- Percentage of successive RR intervals that differ by more than 50 ms (%).