Table 3.
Multiple stepwise regression models predicting 24-hour heart rate variability parameters (n=118)
| Dependent Variable | Independent Variable | Correlation Coefficient | Regression Coefficient (95% Confidence Interval) | P |
|---|---|---|---|---|
| Mean NN | iPTH | −0.25 | −0.03 (−0.05 to −0.01) | 0.007 |
| SDNN | DBP | −0.21 | −0.68 (−1.26 to −0.10) | 0.02 |
| SDANN | Hemoglobin | 0.22 | 0.58 (0.10 to 1.07) | 0.02 |
| SDANN | Calcium | −0.19 | −8.66 (−16.96 to −0.35) | 0.04 |
| rMSSD | Hemoglobin | 0.31 | 0.13 (0.06 to 0.20) | 0.001 |
| rMSSD | Triglyceride | −0.18 | −1.63 (−3.26 to −0.00) | 0.05 |
| pNN50% | SBP | −0.27 | −0.05 (−0.08 to −0.02) | 0.004 |
| pNN50% | Glucose | 0.19 | 0.33 (0.01 to 0.65) | 0.04 |
| Mean heart rate | iPTH | 0.26 | 0.00 (0.00 to 0.01) | 0.004 |
| ln VLF | Albumin | 0.22 | 0.04 (0.01 to 0.07) | 0.02 |
| ln VLF | Hemoglobin | 0.33 | 0.01 (0.01 to 0.02) | <0.001 |
| ln VLF | Phosphorus | 0.22 | 0.11 (0.02 to 0.21) | 0.02 |
| ln VLF | Triglyceride | −0.29 | −0.26 (−0.42 to −0.10) | 0.002 |
| ln VLF | Age | −0.26 | −0.02 (−0.03 to −0.01) | 0.005 |
| ln VLF | iPTH | −0.20 | 0.00 (0.00 to 0.00) | 0.04 |
| ln LF | Age | −0.35 | −0.04 (−0.05 to −0.02) | <0.001 |
| ln LF | Hemoglobin | 0.30 | 0.02 (0.01 to 0.03) | 0.001 |
| ln LF | Triglyceride | −0.22 | −0.27 (−0.50 to −0.04) | 0.02 |
| ln HF | BMI | −0.23 | −0.12 (−0.21 to −0.03) | 0.01 |
| ln LF/HF | Albumin | 0.32 | 0.05 (0.02 to 0.08) | <0.001 |
| ln LF/HF | Phosphorus | 0.22 | 0.12 (0.02 to 0.21) | 0.02 |
Mean NN, mean normal-to-normal R–R intervals; iPTH, intact parathyroid hormone; SDNN, SD of normal-to-normal R–R intervals; DBP, diastolic BP; SDANN, SD of 5-minute average of normal R–R intervals; rMSSD, root mean square of differences between adjacent normal R–R intervals; pNN50%, proportion of adjacent RR intervals differing by >50 ms over 24 hours; SBP, systolic BP; VLF, very low frequency; LF, low frequency; HF, high frequency; BMI, body mass index.