Table 2 Comparisons of the heart rate variability indices between survivors and non-survivors at 8-year follow-up.

From: Heart rate variability as an independent predictor for 8-year mortality among chronic hemodialysis patients

 

Survivors (n = 85)

Non-survivors (n = 79)

p-value

Before the index hemodialysis session+

VLF-0

4.60 (3.77–5.51)

4.14 (3.07–5.68)

0.269

TP-0

5.28 (4.26–6.28)

5.21 (4.12–6.37)

0.813

Variance-0

5.54 (4.61–6.35)

5.27 (4.16–6.55)

0.676

nLF-0

41.40 (28.63–62.70)

37.60 (19.30–51.40)

0.177

nHF-0

31.55 (19.53–45.08)

31.40 (21.05–38.43)

0.417

LF/HF-0

0.20 (0.01–1.20)

0.05 (0.01–0.81)

0.472

Initial phase of the index hemodialysis session

VLF-1

4.76 (4.12–5.98)

5.24 (4.10–6.04)

0.858

TP-1

5.58 (4.69–6.49)

5.69 (4.53–6.60)

0.973

Variance-1

5.71 (4.87–6.65)

5.71 (4.55–6.73)

0.954

nLF-1

47.20 (32.10–66.60)

44.70 (26.30–61.70)

0.338

nHF-1

30.30 (19.40–43.10)

29.40 (21.30–41.90)

0.908

LF/HF-1

0.41 (0.01–1.15)

0.33 (0.01–0.99)

0.671

Middle phase of the index hemodialysis session

VLF-2

5.47 (4.29–6.22)

5.29 (4.25–6.16)

0.722

TP-2

5.86 (5.17–6.94)

5.94 (4.80–7.28)

0.991

Variance-2

5.99 (5.05–6.97)

5.96 (4.98–7.31)

0.794

nLF-2

48.40 (32.70–66.70)

46.70 (30.50–60.20)

0.448

nHF-2

28.00 (19.40–39.10)

29.00 (19.20–36.50)

0.982

LF/HF-2

0.47 (0.01–1.15)

0.44 (0.01–1.04)

0.901

Late phases of the index HD session+

VLF-3

5.33 (3.94–6.47)

4.94 (3.96–6.17)

0.522

TP-3

5.83 (4.79–7.19)

5.67 (4.61–7.19)

0.580

Variance-3

6.05 (4.92–7.08)

5.75 (4.76–7.16)

0.558

nLF-3

47.85 (31.05–67.90)

44.65 (277.78–63.80)

0.750

nHF-3

25.00 (18.88–38.43)

28.00 (18.95–38.20)

0.837

LF/HF-3

0.52 (0.01–1.25)

0.50 (0.01–1.14)

0.735

  1. Notes: Values are presented as median (interquartile range). P-value was calculated using an independent Student’s t-test. HRV-0, -1, -2, and -3 were HRV measured before hemodialysis, and at initial, middle, and late phases of the index hemodialysis session, respectively.
  2. Units: Ln (ms2) in VLF, TP, and Variance; Ln (ratio) in LF/HF ratio; normalized unit in nLF and nHF.
  3. Abbreviations: Ln, nature logarithmical; nHF, normalized high-frequency; nLF, normalized low-frequency; TP, total power; Variance, the variance of the R-R intervals; VLF, very-low-frequency.