Banze Denise, Calderwood Claire J, Nhamuave Celina, Marambire Edson T, Mfinanga Alfred, Larsson Leyla, Malhotra Akanksha Mimi, Minja Lilian T, Ivanova Olena, Zurba Lindsay, Heinrich Norbert, Ferrand Rashida A, Fielding Katherine, Kranzer Katharina, Rachow Andrea, Hurst John R, Khosa Celso
CIH Center for International Health, University Hospital, LMU Munich, Munich, Germany.
Instituto Nacional de Saúde, Marracuene, Mozambique.
ERJ Open Res. 2025 Jul 21;11(4). doi: 10.1183/23120541.00932-2024. eCollection 2025 Jul.
The Global Lung Function Initiative (GLI) and American Thoracic Society recently endorsed a race-composite spirometry reference equation ("GLI Global"). Africa (outside North Africa) is not represented in the underlying dataset; GLI Global has not been evaluated in the region. We evaluated the fit and diagnostic implications of GLI and African (identified by scoping review) reference equations in three East/Southern African countries.
Among healthy participants from a tuberculosis household contact cohort study in Mozambique, Tanzania and Zimbabwe (age ≥10 years) with post-bronchodilator spirometry we calculated forced expiratory volume in 1 s (FEV), forced vital capacity (FVC) and FEV/FVC z-scores using different equations, the proportion of people with obstructive airways disease or preserved-ratio-impaired spirometry by different equations. We compared these measures across reference equations.
In total, 806 healthy people had good-quality post-bronchodilator spirometry. Across GLI equations, "African American" fitted best (mean±sd FEV z-score -0.12±1.20, mean FVC z-score -0.35±1.19). Compared with "African American", GLI Global resulted in twice as many people being identified as having preserved-ratio impaired spirometry (22% 11%) with a similar proportion having obstruction (4.2% 3.8%). Reference equations developed in Africa conferred similar fit compared with the GLI African American equation.
Reference equations have clinical and public health implications that demand careful consideration, particularly in resource-constrained environments. Use of GLI Global may result more people being identified as having lung function impairment. Further work that includes clinical outcomes is needed to ensure that GLI Global is globally representative. The key limitation of this work is the potential for people with undiagnosed respiratory disease to have been included in the analysis.
全球肺功能倡议组织（GLI）和美国胸科学会最近认可了一种种族综合肺量计参考方程（“GLI全球方程”）。非洲（北非以外地区）未纳入基础数据集；GLI全球方程尚未在该地区进行评估。我们在三个东非/南部非洲国家评估了GLI方程和非洲（通过范围综述确定）参考方程的拟合情况及诊断意义。
在莫桑比克、坦桑尼亚和津巴布韦一项结核病家庭接触者队列研究中，对年龄≥10岁且进行了支气管扩张剂后肺量计检查的健康参与者，我们使用不同方程计算1秒用力呼气容积（FEV）、用力肺活量（FVC）和FEV/FVC z评分，以及不同方程诊断为阻塞性气道疾病或比值正常但肺量计异常的人群比例。我们比较了这些参考方程的各项指标。
共有806名健康人进行了高质量的支气管扩张剂后肺量计检查。在GLI方程中，“非裔美国人”方程拟合最佳（平均±标准差FEV z评分为-0.12±1.20，平均FVC z评分为-0.35±1.19）。与“非裔美国人”方程相比，GLI全球方程诊断为比值正常但肺量计异常的人数增加了一倍（22%对11%），阻塞性疾病比例相似（4.2%对3.8%）。在非洲制定的参考方程与GLI非裔美国人方程拟合情况相似。
参考方程具有临床和公共卫生意义，需要仔细考虑，尤其是在资源有限的环境中。使用GLI全球方程可能会使更多人被诊断为肺功能受损。需要进一步开展包括临床结局的研究，以确保GLI全球方程具有全球代表性。这项研究的主要局限性在于分析中可能纳入了未确诊的呼吸道疾病患者。
