Table 1.
Characteristics at baseline according to quartiles of FVC and FEV1-to-FVC ratio
| Quartile |
P value | ||||
|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | ||
| FVC (l) | <3.97 | 3.97– | 4.43– | 4.87– | |
| Age (years) | 53.1 | 51.4 | 49.4 | 47.6 | <0.0001 |
| Current smokers (%) | 49.6 | 42.5 | 36.3 | 38.2 | <0.0001 |
| Inactive (%) | 43.8 | 38.7 | 34.8 | 31.4 | <0.0001 |
| Heavy drinkers (%) | 11.4 | 10.7 | 10.6 | 11.5 | 0.88 |
| Manual (%) | 67.6 | 62.1 | 58.3 | 57.1 | <0.0001 |
| Evidence of CHD (undiagnosed) (%) | 25.9 | 22.1 | 19.4 | 17.0 | <0.0001 |
| Silent MI (ECG) (%) | 2.5 | 3.0 | 1.3 | 0.7 | 0.0002 |
| Arrhythmia (%) | 5.9 | 6.2 | 6.0 | 5.4 | 0.87 |
| BMI (mg/k2) | 25.6 | 25.5 | 25.5 | 25.0 | <0.0001 |
| HDL cholesterol (mmol/l) | 1.14 | 1.15 | 1.15 | 1.17 | 0.11 |
| Triglycerides (mmol/l) | 1.76 | 1.72 | 1.71 | 1.57 | <0.0001 |
| Cholesterol (mmol/l) | 6.24 | 6.28 | 6.30 | 6.16 | 0.12 |
| sBP (mmHg) | 148.1 | 145.6 | 145.4 | 143.1 | <0.0001 |
| Glucose (mmol/l) | 5.53 | 5.47 | 5.47 | 5.42 | <0.0001 |
| CRP (mg/l) | 1.97 | 1.31 | 1.11 | 0.91 | <0.0001 |
| IL-6 (pg/ml) | 2.89 | 2.39 | 2.14 | 2.01 | <0.0001 |
| WCC (×109/l) | 7.17 | 6.95 | 6.89 | 6.82 | <0.0001 |
| GGT (IU/l) | 16.4 | 15.2 | 14.7 | 13.7 | <0.0001 |
| FEV1-to-FVC ratio | <0.71 | 0.71– | 0.77– | 0.82– | |
| Age (years) | 52.2 | 50.8 | 49.7 | 48.7 | <0.0001 |
| Current smokers (%) | 57.9 | 46.8 | 37.0 | 25.2 | <0.0001 |
| Inactive (%) | 41.1 | 42.3 | 33.1 | 32.2 | <0.0001 |
| Heavy drinkers (%) | 15.2 | 12.3 | 9.4 | 9.1 | <0.0001 |
| Manual (%) | 71.2 | 64.0 | 56.8 | 53.0 | <0.0001 |
| Evidence of CHD (undiagnosed) (%) | 25.0 | 20.2 | 18.8 | 20.5 | 0.001 |
| Silent MI (ECG) (%) | 2.3 | 1.5 | 2.0 | 1.8 | 0.57 |
| Arrhythmia (%) | 6.3 | 5.5 | 5.8 | 5.7 | 0.87 |
| BMI (kg/m2) | 24.7 | 25.4 | 25.5 | 26.0 | <0.0001 |
| HDL cholesterol (mmol/l) | 1.17 | 1.15 | 1.14 | 1.14 | <0.0001 |
| Triglycerides (mmol/l) | 1.60 | 1.75 | 1.69 | 1.72 | <0.0001 |
| Cholesterol (mmol/l) | 6.09 | 6.32 | 6.27 | 6.31 | <0.0001 |
| sBP (mmHg) | 146.8 | 146.3 | 144.7 | 144.4 | <0.0001 |
| Glucose (mmol/l) | 5.42 | 5.42 | 5.48 | 5.53 | 0.001 |
| CRP (mg/l) | 1.68 | 1.28 | 1.19 | 1.03 | <0.0001 |
| IL-6 (pg/ml) | 2.80 | 2.32 | 2.23 | 2.08 | <0.0001 |
| WCC (×109/l) | 7.32 | 7.03 | 6.89 | 6.62 | <0.0001 |
| GGT (IU/l) | 15.0 | 15.2 | 14.6 | 14.9 | 0.77 |
Data are means unless otherwise stated. The numbers in bold indicate the range of FVC and FEV1-to-FVC ratio for the four quartiles. WCC, white cell count.