Moreover, there were significant differences in BMI, smoking index, FVC, FEV1/FVC, VA, DLCO, platelet count, hemoglobin, albumin, aspartate aminotransferase, creatinine and cystatin C when the study population II was classified by FVC/DLCO threshold for COPD mortality (all P < 0.05). This evidence concerns the gene CST3 and chronic obstructive pulmonary disease.