Respiratory symptoms and lung function in young adults with severe alpha1-antitrypsin deficiency (PiZZ)

Open Access
Publisher Website
Google Scholar
Abstract
Background: Neonatal screening for alpha1–antitrypsin (AAT) deficiency was undertaken in Sweden between 1972 and 1974 when 129 infants with severe AAT deficiency (phenotype PiZ) were identified. The cohort has been followed up prospectively. Methods: 124 PiZ subjects, still alive and still living in Sweden, were invited to a follow up examination at about 22 years of age. The check up included a clinical examination, spirometric tests, and a questionnaire on smoking habits and respiratory symptoms. Results: Ninety eight subjects (97 PiZZ and 1 PiZ–) subjects attended the follow up. The mean age of the subjects was 22.5 years (range 19.8–24.8). The mean (SD) forced expiratory volume in 1 second (FEV1) was 98 (14)% predicted, vital capacity (VC) was 103 (14)% predicted, and the mean FEV1/VC ratio was 83 (7)%. Eighty six subjects had previously undergone spirometric tests. The median follow up time was 4.3 years (range 0.9–7.3). The mean annual change in FEV1 (% predicted) was –1.2% (95% CI –2.1 to –0.3), in VC (% predicted) was –1.5% (95% CI –2.0 to –0.9), and in the FEV1/VC ratio (%) was –0.3% (95% CI –0.7 to 0.2). Twenty eight individuals (29%) reported recurrent wheezing. Fifteen subjects (15%) had been diagnosed by a physician as having asthma. Eighteen subjects reported that they had smoked at some time; 10 were current smokers. The mean number of pack years among the ever smokers was 3.4 (range 0.6–10.5). Ten of 18 ever-smokers and 18 of 80 non-smokers reported recurrent wheezing (pConclusions: Young PiZ adults have essentially normal lung function, but have a high prevalence of asthma symptoms. Smoking in these individuals is associated with an increased frequency of respiratory symptoms.