At admission, mean PaO2/FiO2 ratio of COPD patients was 231.67 ± 106.40, mean CRP was 57.46 ± 71.84, mean D-dimer 3367.60 ± 7489.84, mean LDH 341.79 ± 147.52, number of peripheral lymphocyte cells 953.42 ± 680.83. The gene discussed is CRP; the disease is chronic obstructive pulmonary disease.