alpha 1-antitrypsin (alpha 1-A.T.) phenotypes were determined in 55 patients with rheumatoid arthritis (R.A.), 33 patients with R.A. and either obstructive airways disease or recurrent chest infections, 49 patients with fibrosing alveolitis (F.A.), 22 patients with R.A. and F.A., and 200 healthy controls.
These findings suggest that the increased susceptibility of patients with Sjögren's syndrome to develop chronic obstructive pulmonary disease is not attributable to an abnormally high frequency of non-MM phenotypes and associated moderately reduced serum levels of alpha-1-AT.
The results suggest a relationship between the PiF allele and chronic obstructive pulmonary disease, which is independent of the serum alpha 1-AT level.
Thus, both shared environmental factors (personal and passive smoking) and shared genetic factors (alpha 1-antitrypsin and a possible direct genetic component) contribute to familial aggregation in COPD.
In a six-month multicenter feasibility and safety study, 20 patients, who all had a congenital deficiency of alpha-1-protease inhibitor (A1PI) of the PiZ phenotype accompanied by a chronic obstructive lung disease, were treated with human-plasma-derived A1PI.
In the case of the other major plasma protease inhibitor, alpha 1-antitrypsin, genetically determined deficiency states are known to increase the risk of chronic obstructive pulmonary disease (COPD) 20- to 30-fold in affected individuals.