TY - JOUR T1 - Reference equations for evaluation of spirometry function tests in South Asia, and among South Asians living in other countries JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.02962-2021 VL - 60 IS - 6 SP - 2102962 AU - Wei Yee Leong AU - Ananya Gupta AU - Mehedi Hasan AU - Sara Mahmood AU - Samreen Siddiqui AU - Sajjad Ahmed AU - Ian Y. Goon AU - Marie Loh AU - Theresia H. Mina AU - Benjamin Lam AU - Yik Weng Yew AU - Joanne Ngeow AU - Jimmy Lee AU - Eng Sing Lee AU - Elio Riboli AU - Paul Elliott AU - Geak Poh Tan AU - Sanjay H. Chotirmall AU - Ananda R. Wickremasinghe AU - Jaspal S. Kooner AU - Khadija I. Khawaja AU - Prasad Katulanda AU - Malay K. Mridha AU - Sujeet Jha AU - Anjana Ranjit Mohan AU - Guha Pradeepa AU - Anuradhani Kasturiratne AU - John C. Chambers Y1 - 2022/12/01 UR - http://erj.ersjournals.com/content/60/6/2102962.abstract N2 - Background There are few data to support accurate interpretation of spirometry data in South Asia, a major global region with a high reported burden of chronic respiratory disease.Method We measured lung function in 7453 healthy men and women aged ≥18 years, from Bangladesh, North India, South India, Pakistan and Sri Lanka, as part of the South Asia Biobank study. First, we assessed the accuracy of existing equations for predicting normal forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and FEV1/FVC ratio. Then, we used our data to derive (n=5589) and internally validate (n=1864) new prediction equations among South Asians, with further external validation among 339 healthy South Asians living in Singapore.Results The Global Lung Initiative (GLI) and National Health and Nutrition Examination Survey consistently overestimated expiratory volumes (best fit GLI-African American, mean±sd z-score: FEV1 −0.94±1.05, FVC −0.91±1.10; n=7453). Age, height and weight were strong predictors of lung function in our participants (p<0.001), and sex-specific reference equations using these three variables were highly accurate in both internal validation (z-scores: FEV1 0.03±0.99, FVC 0.04±0.97, FEV1/FVC −0.03±0.99) and external validation (z-scores: FEV1 0.31±0.99, FVC 0.24±0.97, FEV1/FVC 0.16±0.91). Further adjustment for study regions improves the model fit, with highest accuracy for estimation of region-specific lung function in South Asia.Conclusion We present improved equations for predicting lung function in South Asians. These offer the opportunity to enhance diagnosis and management of acute and chronic lung diseases in this major global population.Newly derived spirometry reference equations greatly improve prediction of normal lung function in South Asians, thus filling the long-standing gap of appropriate reference values for this ethnic group https://bit.ly/3H7ZGt5 ER -