Table 1. Demographic and clinical characteristics of the sample across BMI tertiles.
| Whole sample | 1st BMI tertile ≤ 42.99 | 2nd BMI tertile 43.00 − 48.61 | 3rd BMI tertile ≥ 48.62 | P | |
| N | 262 | 87 | 87 | 88 | |
| Age (years) | 43.1±11.8 | 43.0±13.2 | 41.7±10.2 | 44.7±11.8 | 0.234 |
| Sex (% female) | 74.8 | 72.4 | 77.0 | 75.0 | 0.783 |
| Ethnicity (%) | 0.585 | ||||
| White European | 90.8 | 90.0 | 95.5 | 87.9 | |
| Asian | 5.6 | 5.0 | 2.3 | 8.6 | |
| Black African/Caribbean | 2.8 | 2.5 | 2.3 | 3.4 | |
| Other | 0.7 | 2.5 | 0.0 | 00 | |
| Weight (kg) | 132.1±24.7 | 112.6±14.7 | 129.1±15.6 | 154.2±22.3 | <0.001 |
| Body mass index (BMI, kg/m2) | 47.0±7.9 | 39.4±2.6 | 45.8±1.6 | 55.8±6.6 | <0.001 |
| Waist circumference (cm) | 131.6±14.5 | 123.8±11.8 | 128.6±12.7 | 142.4±12.5 | <0.001 |
| Systolic blood pressure (mmHg) | 140.9±17.7 | 136.0±14.5 | 140.4±17.0 | 146.4±20.0 | 0.009 |
| Diastolic blood pressure (mmHg) | 85.2±11.7 | 83.3±9.7 | 85.5±11.4 | 86.9±13.6 | 0.263 |
| Diabetes (%) | 26.3 | 24.1 | 18.4 | 36.4 | 0.022 |
| Hypertension (%) | 34.4 | 31.0 | 26.4 | 45.5 | 0.022 |
| Arthritis (%) | 24.0 | 21.8 | 19.5 | 30.7 | 0.190 |
| Obstructive sleep apnoea (OSA, %) | 25.6 | 16.1 | 26.4 | 34.1 | 0.024 |
| Cardiovascular disease (CVD, %) | 11.1 | 9.2 | 5.7 | 18.2 | 0.026 |
| Smoking (%) | 25.5 | 31.7 | 23.0 | 22.2 | 0.655 |
| Alcohol consumption (%) | 64.7 | 62.9 | 81.0 | 52.9 | 0.004 |
| IWQOL-Lite (%) Total | 39.5±22.1 | 49.0±23.3 | 38.5±19.9 | 32.1±20.2 | <0.001 |
| Physical function | 42.4±25.3 | 54.1±24.9 | 40.4±23.6 | 34.1±23.7 | <0.001 |
| Self-esteem | 26.2±27.5 | 30.4±30.5 | 24.1±24.4 | 24.5±27.5 | 0.286 |
| Sexual life | 41.9±35.9 | 47.3±36.9 | 43.5±35.6 | 35.2±34.7 | 0.128 |
| Public distress | 40.5±28.9 | 56.6±31.5 | 38.9±25.2 | 27.7±22.7 | <0.001 |
| Work | 51.2±30.3 | 61.6±30.4 | 46.1±27.4 | 47.1±31.3 | 0.003 |
| EQ5D | |||||
| Mobility problems % | 66.7 | 55.9 | 63.0 | 80.3 | 0.006 |
| Self care problems % | 35.7 | 29.9 | 27.2 | 50.0 | 0.006 |
| Anxiety/depression problems % | 75.3 | 73.1 | 75.6 | 77.0 | 0.864 |
| Pain/discomfort problems % | 85.3 | 80.0 | 86.3 | 89.3 | 0.272 |
| Usual activities problems % | 69.0 | 58.0 | 70.4 | 77.6 | 0.036 |
| Perceived health status | 44.0±20.1 | 47.4±19.4 | 42.4±19.0 | 42.9±21.8 | 0.303 |
| HADS Total score | 19.6±7.7 | 19.0±7.6 | 20.2±7.8 | 19.6±7.9 | 0.654 |
| HADS anxiety score | 10.4±4.5 | 10.5±4.3 | 10.7±4.8 | 10.2±4.5 | 0.780 |
| HADS depression score | 9.1±4.0 | 8.6±4.0 | 9.3±3.9 | 9.3±4.1 | 0.436 |
| Anxiety symptoms ≥8 (%) | 70.3 | 74.0 | 68.7 | 68.8 | 0.716 |
| Depression symptoms ≥8 (%) | 66.2 | 62.3 | 72.5 | 63.2 | 0.333 |
| Severe anxiety symptoms ≥11 (%) | 48.3 | 50.7 | 48.2 | 46.3 | 0.860 |
| Severe depression symptoms ≥11 (%) | 40.4 | 33.3 | 42.5 | 44.7 | 0.338 |
Data are percentages and means ± standard deviations. HADS = Hospital anxiety and depression scale.