PMCH and chronic obstructive pulmonary disease: The analysis of hematological parameters (Table 6) revealed statistically significantly increased values of erythrocytes, hemoglobin, MCH, and neutrophils in the COPD group compared to the control group of nonsmokers without COPD (p < 0.05), while the hematocrit value was statistically significantly increased compared to both control groups (p < 0.001).