Lung function parameters among Australian Aboriginal ‘apparently healthy’ adults: an Australian Caucasian and Global Lung Function Initiative (GLI-2012) various ethnic norms comparative study

Comparison of diffusing capacity of carbon monoxide (DLCO) and total lung capacity (TLC) between Indigenous Australians and Australian Caucasian adults

“…There have been only a few studies in the past illustrating the spirometry patterns among the Indigenous Australian population [ 39 – 43 ]. Some studies have demonstrated FEV 1 and FVC values to be 20 to 30% lower [ 43 ], yet with a nearly preserved FEV 1 /FVC ratio [ 11 , 14 ] among the Indigenous Australian population in comparison to non-Indigenous Australians. One previous study in the Australian setting has compared normative references for DLCO among middle aged Australians with other reference equations [ 44 ].…”

“…Currently there are no well-established spirometry normative reference equations for the adult Indigenous Australian population and a recent study including children and adults with a smaller samples size has shown the GLI-2012 reference equation do not fit FEV 1 or FVC for any other ethnic groups [ 48 ]. Similarly, our recently published study involving older adults demonstrated that the GLI-2012 norms do not fit for Australian Indigenous adults regardless of which ethnicity option was selected, including “others/mixed” [ 14 ].…”

“…Study participants included were Indigenous Australian and Australian Caucasian adults living in the TEHS region, who underwent a pulmonary function test between 2012 and 2020 and were referred for PFTs by a primary health practitioner, respiratory specialist or other specialist physician as a part of routine clinical care. A large part of the methodology of this study has been described in our earlier report [ 14 ].…”

“…All PFTs including DLCO and TLC were performed according to the American thoracic and the European respiratory societies guidelines/recommendations, including calibration of equipment and quality assurance [ 16 , 31 ] and as detailed in our previous reports [ 11 , 14 ]. For measuring TLC and DLCO, the portable single-breath diffusing capacity device (EasyOne Pro®, ndd Medical Technologies) was used [ 32 , 33 ].…”

“…Recent work has sought to address this gap in the literature with reports demonstrating significantly reduced Forced Vital Capacity (FVC) and Forced Expiratory Volume in one second (FEV 1 ), yet typically nearly preserved FEV 1 /FVC ratio [ 11 – 13 ]. Moreover, a recent study from our centre found the Global Lung function Initiative (GLI-2012) norms do not fit for Indigenous Australian adults, regardless of which ethnicity option was selected, including “others/mixed” [ 14 ]. Normative reference values for diffusing capacity of carbon monoxide (DLCO) and total lung capacity (TLC) have also yet to be established within the Indigenous Australian population [ 15 ].…”