| OSAHS(n = 441) | Non-OSAHS(n = 97) | p Value | |
| Age (years) | 54.9 | 50.7 | 0.002 |
| % female | 16 | 25 | 0.014 |
| BMI (kg/m2) | 36.9 | 33.3 | 0.001 |
| Collar size (cm) | 45.0 | 43.2 | 0.003 |
| Epworth score | 13.0 | 12.7 | 0.752 |
| Systolic BP (mm Hg) | 141 | 130 | <0.001 |
BMI, body mass index; OSAHS, obstructive sleep apnoea-hypopnoea syndrome.