Table 2.
Heart rate and heart rate variability
| a) Heart rate and heart rate variability of Covid-19 group and control group | ||||
|---|---|---|---|---|
| Variables | Absolute values ± SD | p values | Effect size | |
| Covid-19 (COV, n = 30) | Control (CON, n = 30) | COV vs. CON | COV vs. CON | |
| HR SU1, bpm | 62.97 ± 11.1 | 57.07 ± 10.86 | 0.042* | 0.54 |
| RMSSD SU1, ms | 1.84 ± 0.21 | 1.99 ± 0.27 | 0.018* | 0.63 |
| Respiratory rate SU1, 1/min | 11.59 ± 3.7 | 11.27 ± 3.28 | 0.725 | 0.09 |
| HR ST, bpm | 86.7 ± 10.74 | 75.07 ± 12.77 | 0.001* | 0.99 |
| RMSSD ST, ms | 1.43 ± 0.17 | 1.58 ± 0.2 | 0.004* | 0.78 |
| Respiratory rate ST, 1/min | 11.41 ± 3.21 | 11.24 ± 3.04 | 0.941 | 0.06 |
| HR SU2, 1/min | 62.22 ± 10.71 | 57.35 ± 10.96 | 0.087 | 0.45 |
| RMSSD SU2, ms | 1.92 ± 0.18 | 2.01 ± 0.26 | 0.143 | 0.38 |
| Respiratory rate SU2, 1/min | 11.27 ± 3.5 | 11.17 ± 3.14 | 0.909 | 0.03 |
| ∆ HR SU1-ST | 23.74 ± 6.95 | 18.01 ± 7.56 | 0.003* | 0.79 |
| ∆ HR ST-SU2 | 24.48 ± 6.93 | 17.72 ± 7.68 | 0.001* | 0.92 |
| ∆ RMSSD SU1-ST | 0.41 ± 0.2 | 0.41 ± 0.24 | 0.924 | 0.03 |
| ∆ RMSSD ST-SU2 | 0.49 ± 0.21 | 0.43 ± 0.24 | 0.321 | 0.26 |
| HR SU1/ST | 0.73 ± 0.077 | 0.76 ± 0.08 | 0.082 | 0.46 |
| HR ST/SU2 | 1.41 ± 0.15 | 1.32 ± 0.15 | 0.029* | 0.58 |
| RMSSD SU1/ST | 1.3 ± 0.16 | 1.27 ± 0.18 | 0.586 | 0.15 |
| RMSSD ST/SU2 | 0.75 ± 0.1 | 0.79 ± 0.1 | 0.101 | 0.31 |
| b) Heart rate and heart rate variability of Covid-19 group (moderate and severe symptoms) and control group | ||||
|---|---|---|---|---|
| Variables | Absolute values ± SD | p values | Effect size | |
| Covid-19 moderate and severe symptoms (COVS, n = 17) | Control (CON, n = 30) | COVS vs. CON | COVS vs. CON | |
| HR SU1, bpm | 60.39 ± 9.26 | 57.07 ± 10.86 | 0.294 | 0.32 |
| RMSSD SU1, ms | 1.85 ± 0.24 | 1.99 ± 0.27 | 0.067 | 0.57 |
| Respiratory rate SU1, 1/min | 12.13 ± 4.17 | 11.27 ± 3.28 | 0.435 | 0.24 |
| HR ST, bpm | 85.23 ± 9.53 | 75.07 ± 12.77 | 0.006* | 0.87 |
| RMSSD ST, ms | 1.42 ± 0.17 | 1.58 ± 0.2 | 0.008* | 0.84 |
| Respiratory rate ST, 1/min | 11.96 ± 3.77 | 11.24 ± 3.04 | 0.479 | 0.22 |
| HR SU2, 1/min | 59.79 ± 9.05 | 57.35 ± 10.96 | 0.440 | 0.24 |
| RMSSD SU2, ms | 1.92 ± 0.2 | 2.01 ± 0.26 | 0.230 | 0.37 |
| Respiratory rate SU2, 1/min | 11.95 ± 3.81 | 11.17 ± 3.14 | 0.455 | 0.23 |
| ∆ HR SU1-ST | 24.84 ± 7.47 | 18.01 ± 7.56 | 0.004* | 0.91 |
| ∆ HR ST-SU2 | 25.44 ± 7.13 | 17.72 ± 7.68 | 0.001* | 1.03 |
| ∆ RMSSD SU1-ST | 0.43 ± 0.2 | 0.41 ± 0.24 | 0.860 | 0.05 |
| ∆ RMSSD ST-SU2 | 0.5 ± 0.21 | 0.43 ± 0.24 | 0.327 | 0.3 |
| HR SU1/ST | 0.71 ± 0.08 | 0.76 ± 0.08 | 0.041 | 0.64 |
| HR ST/SU2 | 1.44 ± 0.15 | 1.32 ± 0.15 | 0.015* | 0.77 |
| RMSSD SU1/ST | 1.31 ± 0.15 | 1.27 ± 0.18 | 0.490 | 0.21 |
| RMSSD ST/SU2 | 0.74 ± 0.1 | 0.79 ± 0.1 | 0.125 | 0.48 |
Significant differences emphasized in bold. Data are expressed as mean ± standard deviation (SD) for Covid-19 group (COV) with moderate and severe symptoms (COVS) and control group (CON)
HR heart rate; RMSSD root mean square of successive differences (log-transformed); ∆ HR SU1-ST absolute difference of the heart rate between supine 1 and standing; ∆ HR ST-SU2 absolute difference of the heart rate between standing and supine 2; ∆ RMSSD SU1-ST absolute difference of the RMSSD value between supine 1 and standing; HR SU1/ST ratio of the heart rate of supine 1 and standing; HR ST/SU2 ratio of the heart rate of standing and supine 2; RMSSD SU1/ST: ratio of the RMSSD value of supine 1 and standing; RMSSD ST/SU2: ratio of the RMSSD value of standing and supine 1
* ≤ 0.05 significant value
Effect size Cohen’ d: ≥ 0.2 small effect; ≥ 0.5 medium effect; ≥ 0.8 large effect