Patients’ characteristics according to OSA severity
| Controls AHI<5 | Mild 5≤AHI<15 | Moderate 15≤AHI<30 | Severe AHI≥30 | |
| N | 58 | 97 | 237 | 501 |
| Male n (%) | 30 (52) | 55 (57) | 168 (71) | 392 (78)* |
| Age (years) | 52.0±13.1 | 56.4±13.6* | 57±11.3* | 56.0±11.5* |
| BMI (kg/m2) | 29.3±7.9 | 29±7.5 | 28.7±6.8 | 30.7±6.9 |
| Hypertension (n (%)) | 33 (56) | 65 (67) | 185 (78) | 413 (82)* |
| Type 2 diabetes (n (%)) | 19 (33) | 48 (50) | 106 (45) | 227 (45%) |
| Dyslipidaemia (n (%)) | 34 (59) | 56 (58) | 138 (58) | 323 (64) |
| SBP (mm Hg) | 126±18 | 131±18 | 134±19* | 134±17* |
| DBP (mm Hg) | 74±15 | 74±12 | 81±13* | 82±12* |
| HR (bpm) | 68±15 | 67±14 | 69±13 | 71±15 |
| PWV (m/s) | 10.1±2.6 | 10.7±3 | 10.3±2.4 | 10.4±2.3 |
| Mean nocturnal SaO2 (%) | 93.6±2.3 | 93.2±2.5 | 93.1±3.1 | 92.6±2.9* |
| SaO2 <90% (%) | 6.1±16.6 | 6.8±14.3 | 6.4±14,1 | 14.0±20.9* |
| ESS score | 7.9±5.7 | 8.5±8.4 | 9.2±6.5 | 10±5.3* |
Results are observed data. They are expressed as mean±SD or n (%). These percentages are before imputation of missing data.
*P value versus controls <0.01.
AHI, Apnoea–Hypopnoea Index (events/hour); BMI, Body Mass Index; DBP, diastolic blood pressure; ESS, Epworth Sleepiness Scale; HR, heart rate; PWV, pulse wave velocity; SaO2, oxygen saturation; SaO2 <90%, percentage of recording time spent at a SaO2 <90%; SBP, systolic blood pressure.