Results indicate a lack of correlation between age and SERPINA1 promoter methylation in ACS patients (r = − 0.071 and p > 0.05) as well as between age and SERPINA1 methylation in both COPD+ (r = − 0.073, p > 0.05) and COPD− groups (r = − 0.166, p > 0.05). This evidence concerns the gene SERPINA1 and chronic obstructive pulmonary disease.