Table 3.
Sex differences in the HRV measures, heart rate, clinical characteristics and blood chemistry
| Mean (SD)a/nb (%) girls | Mean (SD)/n (%) boys | t value/χ2 | P | |
|---|---|---|---|---|
| n | 47 | 24 | ||
| Living with single parent | 12 (25.5%) | 7 (29.2%) | 0.11 | 0.74 |
| At least one parent unemployed | 12 (25.5%) | 6 (25.0%) | 0.00 | 0.96 |
| Both parents of foreign origin | 8 (17.0%) | 2 (8.3%) | 0.99 | 0.32 |
| Number of daily smokers | 6 (12.8%) | 1 (4.212.5%) | 1.33 | 0.25 |
| Physical activity (frequency index) | 3.5 (1.14) | 4.7 (0.82) | −4.44 | <0.001 |
| Irregular eating habits (frequency index) | 2.4 (1.25) | 1.5 (0.98) | 3.03 | 0.003 |
| Late sleeping habits (frequency index) | 2.7 (1.49) | 2.7 (1.65) | −0.07 | 0.94 |
| P−glucose (mmol/L) | 5.52 (0.74) | 5.90 (0.79) | −1.99 | 0.05 |
| Haemoglobin (g/L) | 129.7 (12.25) | 145.5 (10.25) | −5.32 | <0.001 |
| Body Mass Index (kg/m2) | 22.4 (3.73) | 22.3 (2.75) | 0.03 | 0.98 |
| Systolic blood pressure (mmHg) | 112.1 (9.53) | 121.2 (9.75) | −3.79 | <0.001 |
| Heart rate (beats per min) | 76.74 (9.51) | 70.30 (8.75) | 2.77 | 0.007 |
| Log HFc | 5.94 (0.81) | 5.80 (1.17) | 0.60 | 0.55 |
| Log LFd | 5.99 (0.88) | 6.14 (0.97) | −0.64 | 0.52 |
| Log SDNNe | 4.09 (0.32) | 4.17 (0.40) | −0.90 | 0.37 |
aStandard deviation, b Number, c Logarithmically transformed high frequency power of HRV, d Logarithmically transformed low frequency power of HRV, e Logarithmically transformed standard deviation of inter-beat intervals