With the exception of its causal genetic association to chronic airway obstruction, even if not measured at a routine clinical non-research basis, mCRP has been found to be slightly increased in Chronic Obstructive Pulmonary Disease (COPD), and particularly, higher mean CRP titers are related to a larger FEV1 decline, but both previous conditions are affected by smoking, which also leads to high CRP levels [83,297]. This evidence concerns the gene CRP and chronic obstructive pulmonary disease.