Relation of functional characteristics and serum alpha-1-antitrypsin (AAT) concentration in patients with PiMM phenotype and chronic obstructive pulmonary disease (COPD)

IntroductionThe relation of AAT phenotype and COPD still raises lots of controversy. In this study we aimed to investigate relation lung function characteristics, AAT serum level and COPD in smoking and non smoking population.Patients and methodsThis was a prospective non-randomized study in which we evaluated 45 patients with severe (stage IV) COPD. In all patients we determined AAT phenotype, serum AAT levels and lung function tests. We correlated findings in relation to the smoking status.ResultsAll patients were MM type homozygotes. Serum AAT concentrations were within the reference values, amounting to 1.66 g/l in smokers and 1.80 g/l in nonsmokers. There was no significant correlation between serum AAT concentrations and lung function parameters. We have observed the higher mean values of ITGV, RV, TLC and RV/TLC in smokers and a statistically significant difference only in ITGV.ConclusionAll of the investigated patients with severe COPD were MM type homozygotes with normal plasma level of AAT. There was no significant correlation between the phenotype and severity of COPD. We did not find significant relation of plasma AAT level and lung function impairment.