COPD patients with a higher EIA/AAT ratio were significantly older (74.6 (SD: 7.1) vs. 68.2 years (SD: 12); p = 0.048), with higher comorbidity burden (CCI: 5.75 (SD: 1.5) vs. 4.8 (SD: 1.9), p = 0.040), lower AAT levels (mg/dL) (144.7 (SD: 27) vs. 150.1 (SD: 19), p = 0.001) and higher absolute EIA (mg/mL) (2 (SD: 0.4) vs. 1.7 (SD: 0.2), p = 0.001), with a trend towards higher disease severity (BODEx index: 3.6 (SD: 2.0) vs. 2.8 (SD: 1.9), p = 0.1). Here, SERPINA1 is linked to chronic obstructive pulmonary disease.