Abstract:
Objective: The Global Lung Function Initiative (GLI) spirometry equations for “Other” ethnic groups have been recommend for use in Aboriginal Australians until appropriate spirometry equations can be developed. We sought to validate the GLI ‘Other’ equations in healthy Aboriginal Australians.
Methods: Spirometry in Aboriginal Australians with no history of lung disease or tobacco smoking were obtained. Predicted spirometry (forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and FEV1/FVC were calculated from the GLI ‘Caucasian’ and ‘Other’ equations. An a priori agreement was set at a mean Z score <0.5.
Results: Spirometry was available in 87 healthy Aboriginal children and adults (aged 5 to 76 years (48% male)). Mean (SD) predicted FEV1 and FVC derived from the GLI ‘Caucasian’ equations (-1.95 (1.07) and -2.08 (1.06), respectively) were significantly lower than predicted. Similarly, the GLI ‘Other’ equation was a poor predictor of lung function in healthy Aboriginal Australians (FEV1: -1.49 (1.14), FVC: -1.62(1.19)). In contrast, FEV1/FVC Z-scores were not significantly different from zero whether compared with predicted ‘Caucasian’ (0.15 (0.82)) or ‘Other’ (-0.01(0.87)).
Conclusions: The Global Lung Function ‘Caucasian’ and ‘Other’ spirometry equations do not match healthy Aboriginal FEV1 and FVC data. Our data supports the use of GLI ‘Other’ FEV1/FVC to detect obstructive lung disease in Aboriginal Australians
Implications: The use of inappropriate spirometry reference equations can have clinical consequences. Appropriate lung function reference equations for Aboriginal and Torres Strait Islanders are urgently needed.
Selection of appropriate spirometry reference values in Aboriginal Australians
The Global Lung Function ‘Caucasian’ and ‘Other’ spirometry equations do not match healthy Aboriginal FEV1 and FVC data