Table 2: Time domain and frequency domain indices of HRV in the study population.

ControlsNAFLD without diabetesNAFLD with diabetes value

Time domain indices
SDNN (ms)40.730.20.006
(24.6–61.5)(15.5–47.8)(17.59–28.2)
SDSD (ms)24.225.90.009
(17.3–43.2)(8.8–36.8)(9.36–19.6)
pNN50 (%)0.040.040.008
(0.00–0.22)(0.00–0.16)(0.00–0.01)
Frequency domain indices
LF nu40.241.937.80.855
(33.4–53.6)(27.1–52.3)(23.9–53.2)
HF nu29.226.819.70.575
(18.4–43.9)(15.6–36.3)(15.5–38.9)
LF : HF ratio1.51.61.60.843
(1.0–2.6)(1.0–2.2)(0.9–2.9)
Total power (ms2)1166.5658.40.005
(383.5–2312.6)(202.9–1379.2)(173.3–545.4)

Values are expressed as median (IQR); versus control; versus NAFLD without diabetes.
SDNN: standard deviation of all NN intervals; SDSD: standard deviation of differences between adjacent NN intervals; pNN50%: NN50 count divided by the total number of all NN intervals; LF: low frequency (0.04–0.15 Hz); HF: high frequency (0.15–0.40 Hz); nu: normalized unit.