Annual change in FEV1 (% predicted) in the Lung Health Study cohort according to quintiles of CRP levels and smoking status
| Quintile 1 | Quintile 2 | Quintile 3 | Quintile 4 | Quintile 5 | p for trend† | |
|---|---|---|---|---|---|---|
| *Geometric mean value for each quintile of CRP. | ||||||
| †Linear trend from quintile 1 to quintile 5. | ||||||
| The interaction term for smoking status and CRP quintiles was not significant (p = 0.140). | ||||||
| Data are expressed as mean (SD) and are calculated from (FEV1 % predicted in year 1 – FEV1 % predicted in year 5)/5years | ||||||
| Mean CRP (mg/l)* | 0.21 | 0.73 | 1.39 | 2.58 | 7.06 | |
| All participants | 0.43 (1.69) | 0.63 (1.50) | −0.58 (1.62) | −0.81 (1.53) | −0.93 (1.54) | <0.001 |
| Sustained smokers | 1.00 (1.60) | 1.07 (1.44) | −1.03 (1.57) | −1.30 (1.42) | −1.25 (1.52) | 0.002 |
| Intermittent smokers | 0.10 (1.60) | 0.30 (1.37) | −0.38 (1.48) | −0.50 (1.52) | −0.64 (1.44) | <0.001 |
| Sustained quitters | 0.43 (1.57) | 0.15 (1.41) | 0.37 (1.47) | 0.12 (1.37) | −0.15 (1.44) | 0.002 |