Geographical variation in lung function: results from the multicentric cross-sectional BOLD study

• Main Author: Burney, Peter G.
• Publication Date: 2024
• Other Authors: Potts, James, Knox-Brown, Ben, Erhabor, Gregory, Hacene Cherkaski, Hamid, Mortimer, Kevin, Anand, Mahesh Padukudru, Mannino, David M., Cardoso, Joao, Ahmed, Rana, Elsony, Asma, Barbara, Cristina, Nielsen, Rune, Bateman, Eric, Paraguas, Stefanni Nonna, Cher Loh, Li, Rashid, Abdul, Wouters, Emiel F., Franssen, Frits M., Dias, Hermínia Brites, Gislason, Thorarinn, Ghobain, Mohammed A., Biaze, Mohammed El, Agarwal, Dhiraj, Juvekar, Sanjay, Rodrigues, Fatima, Obaseki, Daniel O., Koul, Parvaiz A., Harrabi, Imed, Nafees, Asaad A, Seemungal, Terence, Janson, Christer, Vollmer, William M, Amaral, Andre F., Buist, A Sonia
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://hdl.handle.net/10400.21/18001
• topic: Pneumology; Airflow obstruction; Forced expiratory volume; Forced vital capacity; Global health; Cross-sectional study

Spirometry is used to determine what is "unusual" lung function compared with what is "usual" for healthy non-smokers. This study aimed to investigate regional variation in the forced vital capacity (FVC) and in the forced expiratory volume in one second to FVC ratio (FEV1/FVC) using cross-sectional data from all 41 sites of the multinational Burden of Obstructive Lung Disease study. Participants (5,368 men; 9,649 women), aged ≥40 years, had performed spirometry, had never smoked and reported no respiratory symptoms or diagnoses. To identify regions with similar FVC, we conducted a principal component analysis (PCA) on FVC with age, age2 and height2, separately for men and women. We regressed FVC against age, age2 and height2, and FEV1/FVC against age and height2, for each sex and site, stratified by region. Mean age was 54 years (both sexes), and mean height was 1.69 m (men) and 1.61 m (women). The PCA suggested four regions: 1) Europe and richer countries; 2) the Near East; 3) Africa; and 4) the Far East. For the FVC, there was little variation in the coefficients for age, or age2, but considerable variation in the constant (men: 2.97 L in the Far East to 4.08 L in Europe; women: 2.44 L in the Far East to 3.24 L in Europe) and the coefficient for height2. Regional differences in the constant and coefficients for FEV1/FVC were minimal (<1%). The relation of FVC with age, sex and height varies across and within regions. The same is not true for the FEV1/FVC ratio.