Study objectives: First, to determine the relationships among chronic sputum expectoration (CSE), exacerbations, airflow obstruction, and emphysema in patients with α1-antitrypsin deficiency (α1-ATD) [PiZ]. Second, to use multivariate analysis to determine how these factors influence health status.
Design: Cross-sectional, single-center.
Setting: UK center for α1-ATD, university teaching hospital.
Patients: One hundred seventeen nonsmoking patients underwent lung function testing, high-resolution CT (HRCT) scanning with density mask analysis, and health status assessment using the St. George’s Respiratory Questionnaire (SGRQ) and short form 36 (SF-36) health survey questionnaire.
Results: Patients with CSE (n = 50) had worse postbronchodilator airflow obstruction than those who did not (p = 0.03), with a median FEV1 of 1.15 L (interquartile range [IQR], 0.76 to 1.82) vs 1.44 L (IQR, 0.99 to 2.93), respectively, and higher HRCT scan voxel index (VI) values indicating more extensive emphysema (patients with CSE: median lower zone VI, 50; IQR, 28 to 61; patients without CSE: median lower zone VI, 41; IQR, 5 to 53; p = 0.04). Patients with CSE also had worse health status, as assessed by the SGRQ (p < 0.01 for all domains) and SF-36 questionnaire (p < 0.05 for seven of nine domains). Exacerbation frequency was greater in those patients with CSE (p < 0.001), with a median of two episodes per year (IQR, 1 to 3) vs 0.66 episodes per year (IQR, 0 to 2) for those without CSE. Stepwise linear regression analysis revealed FEV1, exacerbation frequency, and lower zone VI to be the most important predictors of health status.
Conclusions: Among patients with α1-ATD, those with CSE expectoration exhibit greater physiologic impairment and more extensive emphysema than those without. This is reflected in an inferior health status, which is also influenced independently by an increased exacerbation frequency in those with CSE.