Critical analysis of spirometric patterns in correlation to chest computed tomography among adult indigenous Australians with chronic airway diseases.

Abstract

Background: There is sparse literature evidence in the spirometric patterns of adult Indigenous Australians with and without chest computed tomography (CT) proven chronic airway diseases (CADs).Methods: Participants spirometry testing graded as acceptable for quality and had a chest CT scan showing radiographic evidence of CADs were included for analysis.Results: Of the 1350 spirometric tests performed between 2012 and 2020, a total of 214 patients with a mean age of 53 years and 54% females were eligible to be included. One-third (33%) had normal chest CT, 32% had predominant COPD, 19% bronchiectasis and 16% combined COPD & bronchiectasis. Percentage predicted values for Forced Vital Capacity (FVC) and Forced Expiratory Volume in one second (FEV(1)) both pre- and post- bronchodilator were significantly reduced for all participants - FVC: CT normal 64%, 65%; COPD 57%, 61%; bronchiectasis 54%, 54%; combined COPD & bronchiectasis 50%, 53%. FEV(1): CT normal 61%, 63%; COPD 45%, 48%; bronchiectasis 48%,51%; combined COPD & bronchiectasis 36%,40%. FEV(1)/FVC was only reduced for CT abnormality patients - CT normal 95%,97%; COPD 76%,76%; bronchiectasis 87%,89%; combined COPD & bronchiectasis 71%,72%.Conclusions: Restrictive spirometric pattern is common and an obstructive pattern with COPD, in isolation or when COPD coexists with bronchiectasis.