Chest computed tomography findings among adult Indigenous Australians in the Northern Territory of Australia

Introduction: There is sparse evidence in the literature in relation to the chest computed tomography (CT) findings among adult Indigenous Australians with chronic respiratory conditions. 

Methods: In this retrospective study, patients who underwent chest CT between 2012 and 2020 among those referred to undergo lung function tests (spirometry) were assessed for the prevalence of abnormal chest CT radiological findings. 

Results: Of the 402 patients (59% female) included in this study, 331 (82%) had an abnormality identified on chest CT. Most abnormalities occurred alongside one (25%) or multiple (46%) other CT abnormalities. Airway disease ((AD) (including, emphysema, airway wall thickening and small airway disease) (35%), atelectasis: segmental or lobar collapse (27%), inflammatory opacities (24%) and bronchiectasis (23%) were the most common findings. AD and bronchiectasis were also the most common concurrent abnormalities in 40–50%. Other CT abnormalities noted in isolation or in combination with other CT findings were lung nodules (19%), lymph node enlargement (17%), consolidation or mass (17%), followed by lung cysts, ground-glass opacity, lung parenchymal architectural distortion, cavitating lung lesions and chronic pleural effusion were observed in ≤10%. Predictive models for odds of abnormality and outcomes showed age, smoking and underweight were associated with AD, and male sex and very remote residence were associated with bronchiectasis. 

Conclusion: This study has illustrated that Indigenous Australian adults have a high prevalence of multiple chest CT abnormalities that may impose unprecedented diagnostic and therapeutic challenges in this population. Further studies are warranted to determine the long-term implications and prognostic significance of the CT findings as demonstrated in this study.