CLINICAL-FEATURES OF INDIVIDUALS WITH PI(ASTERISK)SL PHENOTYPE OF ALPHA(1)-ANTITRYPSIN DEFICIENCY

This report describes the clinical characteristics of a group of 59 in dividuals with the PISZ phenotype and alpha(1)-antitrypsin (alpha(1)- AT) deficiency, identified during recruitment of a registry for subjec ts with severe alpha(1)-antitrypsin deficiency, Currently, 1,129 indiv iduals with levels of alpha(1)-AT of 11 mu M or below have been enroll ed in this registry. individuals with the SZ phenotype whose alpha(1)- AT levels are at or below 11 mu M will be followed in the registry; th ose whose levels exceeded 11 mu M had baseline studies and are include d in this report. Baseline pulmonary function tests included spirometr y before and after an inhaled bronchodilator, diffusing capacity for c arbon monoxide (DL(CO)), and chest roentgenograms. Among nonsmokers, s ubjects with the 52 phenotype demonstrated airflow obstruction less fr equently than those with with the-ZZ phenotype. Among ex- and current smokers, the frequency and severity: of airflow obstruction was simila r between Sf and 22 subjects. individuals with the 52 phenotype report ed respiratory symptoms less frequently than did ZZ subjects. Overall, airflow obstruction was less common and milder among PISZ than PI*ZZ subjects. Cigarette smoking correlated more strongly with airflow obs truction among PISZ than PI*ZZ subjects. These observations indicate that in smokers, the PISZ phenotype confers a significant risk of the development of chronic obstructive pulmonary disease (COPD). Of itsel f, except in rare instances in nonsmoking individuals, the PISZ pheno type may confer little or no added risk of developing COPD.