Characteristics and prevalence of conditions and determinants among normal-weight, underweight, pre-obese and obese subjects
| Normal weight | Underweight | p-value | Pre-obesity | p-value | Obesity | p-value | |
| Subjects | 1296 | 86 | 1544 | 596 | |||
| Mean age years | 59.0 | 60.1 | 0.446 | 58.9 | 0.719 | 58.8 | 0.779 |
| Men/women | 44.7%/55.3% | 25.6%/74.4% | 0.001 | 55.4%/44.6% | <0.001 | 45.1%/54.9% | 0.902 |
| Mean FEV1 % predicted | 95 | 87 | <0.001 | 96 | 0.511 | 93 | 0.001 |
| Mean FVC % predicted | 98 | 94 | 0.002 | 97 | <0.001 | 93 | <0.001 |
| Normal spirometry | 77.8% | 67.4% | 0.060 | 82.4% | 0.003 | 84.6% | <0.001 |
| COPD grade 1 | 11.7% | 14.0% | 8.0% | 5.2% | |||
| COPD grade 2 | 8.7% | 14.0% | 8.4% | 8.4% | |||
| COPD grades 3 and 4 | 1.8% | 4.7% | 1.1% | 1.8% | |||
| Never-smokers | 39.2% | 32.6% | 0.004 | 41.6% | 0.001 | 42.6% | 0.072 |
| Former smokers | 36.2% | 26.7% | 0.004 | 39.5% | 0.001 | 37.4% | 0.072 |
| Smokers | 24.2% | 40.7% | 18.9% | 20.0% | |||
| Coronary artery disease | 10.8% | 8.1% | 0.432 | 12.4% | 0.218 | 15.8% | 0.003 |
| Heart failure | 0.8% | 1.2% | 0.758 | 1.0% | 0.732 | 2.3% | 0.008 |
| Hypertension | 24.4% | 22.1% | 0.631 | 34.9% | <0.001 | 50.8% | <0.001 |
| Diabetes | 4.5% | 4.7% | 0.934 | 8.2% | <0.001 | 16.5% | <0.001 |
| Wheeze most days a week | 7.2% | 15.1% | 0.007 | 9.9% | 0.010 | 16.4% | <0.001 |
| mMRC dyspnoea score ≥2 | 10.5% | 23.2% | <0.001 | 15.1% | <0.001 | 27.3% | <0.001 |
| Chronic productive cough | 25.0% | 31.4% | 0.186 | 26.6% | 0.346 | 27.2% | 0.215 |
p-values are versus normal weigh. Subjects with a restrictive spirometric pattern were excluded. FEV1: forced expiratory volume in the first second; FVC: forced vital capacity; COPD: chronic obstructive pulmonary disease; mMRC: modified Medical Research Council.