Augmentation therapy reduces frequency of lung infections in antitrypsin deficiency: a new hypothesis with supporting data.

STUDY
OBJECTIVES: To propose an hypothesis that antiprotease augmentation therapy reduces the incidence of lung infections in alpha(1)-antitrypsin (AAT)-deficient patients, and to present supporting data.
DESIGN: The proposed concept is based on a survey taken via the Internet of patients receiving augmentation therapy for 1 to 10 years compared to similar patients not receiving such therapy.
SETTING: A questionnaire was submitted to patients with a ZZ phenotype for AAT deficiency to determine whether those receiving antitrypsin augmentation therapy were aware of any personal benefit, and whether the therapy had an effect on the frequency of lung infections. PATIENTS: Ninety-six adult patients receiving human alpha(1)-proteinase inhibitor (alpha(1)-PI) responded, as did 47 similar patients not receiving augmentation therapy.
RESULTS: Seventy-four of 89 patients who had received alpha(1)-PI infusions for > 1 year believed that they had definitely benefited from such therapy. Fifty-six of the 74 patients claiming a benefit attributed this to a reduction in the number of lung infections since starting therapy with alpha(1)-PI infusions. Before starting alpha(1)-PI, the majority of patients had three to five infections per year, dropping to zero to one infection per year during alpha(1)-PI therapy (p < 0. 001).
CONCLUSIONS: Replacement therapy for AAT deficiency-associated emphysema appears to be associated with a marked reduction in the frequency and severity of lung infections. This association must be evaluated further in future, more rigid, prospective studies of AAT augmentation therapy. Findings support the hypothesis that antiprotease therapy with alpha(1)-PI reduces the incidence of lung infections in addition to slowing the deterioration of lung function and causing a reduction in mortality.