Table 3. Sensitivity, specificity, ROC curve, and positive and negative predictive values of heart rate variability indices to predict late postmenopausal.
| Variables | ROC (95%CI) | p | Sensitivity | Specificity | PPV | NPV | Cutoff |
|---|---|---|---|---|---|---|---|
| MEANRR | 0.57 (0.48–0.66) | 0.157 | 48.53 (36.2–61.0) | 70.91 (57.1–82.4) | 1.67 | 0.73 | >936.599975586 |
| SDNN | 0.59 (0.50–0.68) | 0.0658 | 80.88 (69.5–89.4) | 43.64 (30.3–57.7) | 1.44 | 0.44 | ≤31.299999237 |
| RMSSD | 0.545 (0.453–0.635) | 0.4008 | 60.29 (47.7–72.0) | 56.36 (42.3–69.7) | 1.38 | 0.70 | ≤21.200000763 |
| RRtri | 0.608 (0.516–0.695) | 0.040a | 88.24 (78.1–94.8) | 32.73 (20.7–46.7) | 1.31 | 0.36 | ≤9.666999817 |
| TINN | 0.583 (0.490–0.671) | 0.1319 | 76.47 (64.6–85.9) | 50.91 (37.1–64.6) | 1.56 | 0.46 | ≤150 |
| LF, ms² | 0.563 (0.471–0.652) | 0.2544 | 69.12 (56.7–79.8) | 54.55 (40.6–68.0) | 1.52 | 0.57 | ≤240 |
| LF, nu | 0.522 (0.430–0.613) | 0.6817 | 52.94 (40.4–65.2) | 63.64 (49.6–76.2) | 1.46 | 0.74 | ≤58.299999237 |
| HF, ms² | 0.581 (0.489–0.669) | 0.1319 | 75.00 (63.0–84.7) | 47.27 (33.7–61.2) | 1.42 | 0.53 | ≤233 |
| HF, nu | 0.520 (0.428–0.611) | 0.7115 | 52.94 (40.4–65.2) | 63.64 (49.6–76.2) | 1.46 | 0.74 | >41.099998474 |
| LF/HF | 0.521 (0.429–0.611) | 0.6984 | 52.94 (40.4–65.2) | 63.64 (49.6–76.2) | 1.46 | 0.74 | ≤1.404000044 |
| SD1 | 0.559 (0.467–0.649) | 0.2718 | 58.82 (46.2–70.6) | 58.18 (44.1–71.3) | 1.41 | 0.71 | ≤14.800000191 |
| SD2 | 0.600 (0.508–0.688) | 0.0604 | 70.59 (58.3–81.0) | 52.73 (38.8–66.3) | 1.49 | 0.56 | ≤36.299999237 |
| SD1/SD2 | 0.505 (0.413–0.596) | 0.9310 | 17.65 (9.5–28.8) | 67.27 (53.3–79.3) | 0.54 | 1.22 | >1.893000007 |
| SAMPEN | 0.544 (0.451–0.634) | 0.4052 | 38.24 (26.7–50.8) | 74.55 (61.0–85.3) | 1.50 | 0.83 | >1.827000022 |
| ALFA1 | 0.545 (0.453–0.635) | 0.3951 | 66.18 (53.7–77.2) | 47.27 (33.7–61.2) | 1.26 | 0.72 | ≤1.129999995 |
| ALFA2 | 0.502 (0.411–0.594) | 0.9645 | 67.65 (55.2–78.5) | 45.45 (32.0–59.4) | 1.24 | 0.71 | ≤0.587000012 |
| ALFA1/ALFA2 | 0.508 (0.416–0.599) | 0.8787 | 80.88 (69.5–89.4) | 30.91 (19.1–44.8) | 1.17 | 0.62 | ≤2.587248325 |
p<0.05. 95%CI: 95% confidence interval; PPV: positive predictive value; NPV: negative predictive value; MEANRR: median of RR intervals/ms; SDNN: mean standard deviation of all normal RRis/ms; RMSSD: square root of the mean of squared differences between successive beat intervals/ms; HF: high frequency; LF: low frequency; LF/HF: low-frequency/high-frequency ratio; SD1: standard deviation of the RRis; SD2: standard deviation of long-term continuous RRis; SD1/SD2: ratio between short and long variations of the intervals; RRtri: triangular index; TINN: RRi triangular interpolation; SAMPEN: sample entropy; ALPHA1: short-term fractal scaling exponent; ALPHA2: long-term fractal scaling exponent; ALPHA1/ALPHA2: short-term fractal scaling exponent/long-term fractal scaling exponent ratio.