PT  - JOURNAL ARTICLE
AU  - Kevin De Soomer
AU  - Evelyn Pauwels
AU  - Hilde Vaerenberg
AU  - Eric Derom
AU  - Lidia Casas
AU  - Johan Verbraecken
AU  - Thérèse Lapperre
AU  - Ellie Oostveen
TI  - Evaluation of the Global Lung Function Initiative reference equations in Belgian adults
AID  - 10.1183/23120541.00671-2021
DP  - 2022 Apr 01
TA  - ERJ Open Research
PG  - 00671-2021
VI  - 8
IP  - 2
4099  - http://openres.ersjournals.com/content/8/2/00671-2021.short
4100  - http://openres.ersjournals.com/content/8/2/00671-2021.full
SO  - erjor2022 Apr 01; 8
AB  - Background Over the past decade, the Global Lung Function Initiative (GLI) Network has published all-age reference equations on spirometry, diffusing capacity of the lung for carbon monoxide (DLCO) and lung volumes.Methods We evaluated the appropriateness of these equations in an adult Caucasian population. Retrospective lung function data on subjects who performed tests prior to a diagnostic sleep investigation were analysed. From the medical records, lung healthy, lifetime nonsmoking, nonobese subjects were selected, resulting in a population of 1311 subjects (68% male; age range 18–88 years).Results Multiple linear regression analysis revealed that lung function z-scores did not differ between subjects with and without sleep apnoea but did depend on height and age. The average forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) z-score was 0 but exhibited an inverse association with height in both sexes (p<0.01). Values of FEV1 and FVC in both sexes were larger than predicted (mean±sd z-score +0.30±0.96 or 104±13% pred; p<0.01). Overall, static lung volumes and DLCO were adequately predicted. However, DLCO z-scores were inversely associated with height in males and age in females (p<0.01). For all lung function indices, the observed scatter was reduced compared with the prediction. Therefore, for all indices <5% of the data were below the GLI-proposed lower limit of normal (LLN) threshold.Conclusion GLI reference equations provide an adequate fit in Belgian adults. However, the GLI-proposed LLN is too low for our Antwerp population, resulting in underdiagnosis of disease. Furthermore, airway obstruction and diffusion disorders might be misclassified due to height and age associations.Overall, GLI reference equations for lung function appropriately describe the data in Belgian adults. However, airway obstruction and diffusion disorders might be misdiagnosed at age and height extremes, and the GLI LLN was too low in this population. https://bit.ly/3jdauLE