Table 1. The basic characteristics of the participants.
| Characteristics | AHI ≤ 15 events/h, n = 156 | AHI > 15 events/h, n = 373 | P value |
| Age, yrs | 58.4 ± 10.7 | 59.2 ± 10.9 | 0.427 |
| Males | 108 (69.2%) | 298 (79.9%) | 0.008 |
| Heart rate | 71.4 ± 10.4 | 73.9 ± 11.8 | 0.017 |
| AHI events/h | 9.4 ± 3.4 | 37.2 ± 16.9 | < 0.001 |
| Epworth sleepiness scale | 4.5 ± 3.9 | 6.2 ± 5.4 | < 0.001 |
| Systolic pressure, mmHg | 128.6 ± 17.1 | 130.9 ± 18.2 | 0.172 |
| Hypertensive patients | 100 (64.1%) | 281(75.3%) | 0.009 |
| Diabetes mellitus | 47 (30.1%) | 146 (39.1%) | 0.050 |
| Dyslipidaemia | 69 (44.2%) | 169 (45.3%) | 0.820 |
| Body mass index, kg/m2 | 26.4 ± 3.4 | 28.1 ± 3.6 | < 0.001 |
| Current or former smoker | 47 (30.1%) | 103 (27.6%) | 0.559 |
| Alcohol abuse | 7 (4.5%) | 26 (7.0%) | 0.282 |
| LDL-C, mmol/L | 2.5 ± 0.9 | 2.5 ± 1.0 | 0.371 |
Data are presented as mean ± SD or n (%). Mann–Whitney and Chi-squared tests were used to assess the differences in the means or proportions between groups. Statistically significant p-values are shown in bold. AHI: apnea–hypopnea index; LDL-C: low density lipoprotein cholesterol.