IL-1 β, but not sIL-1RII, remained significantly higher in COPD patients than in CHF patients and healthy smokers [1.43 (0.57-2.16) vs. 0.48 (0.34-0.88) and 0.47 (0.40-0.89, respectively, p < 0.0006]. This evidence concerns the gene IL1R2 and chronic obstructive pulmonary disease.