Variables | Correlation coefficienta | Annual decline in FEV1 Mean ± SD (mL/yr) | P value |
---|---|---|---|
Categorical variables | Â | Â | Â |
   Gender |  |  | 0.205 |
Male |  | 25.0 ± 28.2 |  |
Female |  | 22.8 ± 24.5 |  |
   Smoking habits |  |  | 0.005 |
Never-smokers |  | 21.7 ± 24.5 |  |
Ex-smokers |  | 26.7 ± 27.6 |  |
Current-smokers |  | 28.5 ± .30.5* |  |
   Smoking indexb |  |  | 0.006 |
0 |  | 21.7 ± 24.5 |  |
0-200 |  | 28.2 ± 29.6 |  |
> 200 |  | 27.0 ± 28.3* |  |
Continuous variables | Â | Â | Â |
   Age | 0.105 |  | 0.001 |
   BMI | 0.038 |  | 0.245 |
   FVC (L) | -0.069 |  | 0.037 |
   FVC % predicted (%) | -0.146 |  | < 0.001 |
   FEV1 (L) | -0.144 |  | < 0.001 |
   FEV1 % predicted (%) | -0.263 |  | < 0.001 |
   FEV1/FVC (%) | -0.278 |  | < 0.001 |
   Serum IgE (Log IU/mL) | 0.097 |  | 0.003 |