| All patients | Group A | Group B | Group C | p-value | |
| Subjects n | 65 | 22 | 22 | 21 | |
| Age yrs | 52±10 | 52±11 | 53±9 | 51±10 | ns |
| Male | 54 (83) | 18 (82) | 21 (96) | 15 (71) | ns |
| Female | 11 (17) | 4 (18) | 1 (4) | 6 (29) | ns |
| BMI kg·m−2 | 34±7 | 32±5 | 34±7 | 36±7 | ns |
| Neck circumference cm | 45.5±3.5 | 45.4±3.7 | 45.3±3.3 | 45.9±3.2 | ns |
| Hypertension | 32 (49) | 11 (50) | 12 (55) | 9 (43) | ns |
| Habitual snoring | 100 | 100 | 100 | 100 | ns |
| SACS | 40±26 | 41±29 | 39±25 | 41±25 | ns |
Data are presented as mean±sd, n (%) or %, unless otherwise stated. BMI: body mass index; SACS: Sleep Apnoea Clinical Score; ns: nonsignificant.