No nap | Nap frequency | P value | |||
1–2 weekly | 3–5 weekly | 6–7 weekly | |||
No (%) | 2014 (58.1) | 667 (19.3) | 411 (11.9) | 370 (10.7) | |
Age (years) (mean±SD) | 56.5 (10.2) | 53.9 (9.1) | 59.6 (9.9) | 63.1 (10.3) | <0.001 |
Men (n (%)) | 843 (41.9) | 303 (45.4) | 205 (49.9) | 208 (56.2) | <0.001 |
Educational status (n (%)) | <0.001 | ||||
High | 472 (23.4) | 195 (29.2) | 87 (21.2) | 49 (13.2) | |
Middle | 536 (26.6) | 195 (29.2) | 125 (30.4) | 84 (22.7) | |
Low | 1006 (50.0) | 277 (41.5) | 199 (48.4) | 237 (64.1) | |
Smoker (n (%)) | 372 (18.5) | 164 (24.6) | 82 (20.0) | 73 (19.7) | 0.008 |
Sedentary behaviour (n (%)) | 1123 (55.8) | 379 (56.8) | 235 (57.2) | 233 (63.0) | 0.084 |
BMI (n (%)) | <0.001 | ||||
Normal | 1008 (50.1) | 321 (48.1) | 170 (41.4) | 125 (33.8) | |
Overweight | 740 (36.7) | 249 (37.3) | 170 (41.4) | 157 (42.4) | |
Obese | 266 (13.2) | 97 (14.5) | 71 (17.3) | 88 (23.8) | |
Sleep duration (hours/night) (mean±SD) | 6.9 (1.1) | 6.9 (1.1) | 7.1 (1.2) | 7.1 (1.2) | 0.010 |
Hypertension (n (%)) | 720 (35.8) | 207 (31.1) | 181 (44) | 207 (56.0) | <0.001 |
Diabetes (n (%)) | 148 (7.4) | 52 (7.8) | 50 (12.2) | 65 (17.6) | <0.001 |
Dyslipidaemia (n (%)) | 286 (14.2) | 82 (12.3) | 82 (20.0) | 102 (27.6) | <0.001 |
Excessive daytime sleepiness (ESS >10)† (n (%)) | 160 (8.3) | 86 (13.5) | 56 (14.4) | 46 (13.0) | <0.001 |
Severity of sleep apnoea‡ (n (%)) | <0.001 | ||||
Normal | 314 (33.1) | 103 (31.6) | 50 (26.0) | 32 (16.8) | |
Mild | 333 (35.1) | 122 (37.4) | 76 (39.6) | 60 (31.4) | |
Moderate | 193 (20.3) | 67 (20.6) | 31 (16.2) | 58 (30.4) | |
Severe | 110 (11.6) | 34 (10.4) | 35 (18.2) | 41 (21.5) | |
Depressive status | 190 (10.1) | 84 (13.4) | 55 (14.4) | 75 (22.3) | <0.001 |
P values from Pearson χ2 or ANOVA where appropriate.
†n=3300.
‡n=1659. Normal: apnoea–hypopnoea index (AHI) <5/hour; mild: AHI between 5 and 15/hour; moderate: between 15 and 30/hour; severe: >30/hour.
ESS, Epworth sleepiness scale.