Background and Aims: Lung function/spirometry testing is a crucial diagnostic tool for assessing respiratory health, particularly in regions with high rates of respiratory disorders. The Top End region in the Northern Territory of Australia covers a vast geographical area and most Indigenous Australians in the region reside in very remote and rural Indigenous communities. Previous reports have indicated a substantial respiratory health burden in the adult Indigenous population in this region. We explored if there were any variations in the spirometry parameters between Indigenous communities amongst adult patients.

Methods: The adult respiratory and sleep service based at the Royal Darwin Hospital visits approximately twenty remote communities each year as a part of respiratory outreach service in the Top End, NT, Australia. Spirometry performed between January 2023 and December 2024 were assessed, involving 13 remote/rural Indigenous communities. Spirometry tests were performed using a portable device.

Results: 257 patients (60.3% female, median age 54 (IQR 46, 63)) were included from 13 communities. The majority of patients were underweight (22.2%) or normal weight (38.1%) and current (63%) or former (30%) smokers. 33 (12.8%) tests were considered failed (test quality E (n = 2) or F (n = 31)). Despite significant variation in age between communities, there were no significant differences in percent predicted values of lung function parameters. Among acceptable spirometry tests, the median percent predicted median FEV1 ranged from 35% to 82%, FVC median 51%–79%, and FEV1/FVC 60%–104%. The prevalence and type of ventilatory impairment varied significantly across communities (No impairment frequency range 0%–33.3%, obstructive 0%–20%, restrictive 0%–55.6% & mixed 32%–81.3%).

Conclusion: Our results indicate there is significant heterogeneity in spirometry parameters between Indigenous communities, which may be related to social determinants, environmental factors, and housing conditions. Further studies are warranted to investigate factors influencing lower lung function values in Indigenous communities.