The Effects of Asthma on the Association Between Pulmonary Function and Obesity: A 16-Year Longitudinal Study

• Published in: Journal of asthma and allergy Vol. 14; pp. 347 - 359
• Main Authors: Huang, Ying-Jhen, Chu, Yi-Chi, Huang, Hung-Ling, Hwang, Jing-Shiang, Chan, Ta-Chien
• Format: Journal Article
• Language: English
• Published: New Zealand Dove Medical Press Limited 01.01.2021; Taylor & Francis Ltd; Dove; Dove Medical Press
• Subjects: Abdomen; Age; Air pollution; Analysis; Asthma; bmi; Body mass index; Disease; fvc; Health aspects; ISO standards; Longitudinal studies; Obesity; Original Research; Outdoor air quality; Periodic health examinations; Physical diagnosis; Public health; pulmonary function; Questionnaires; Respiratory function; Risk factors; Sociodemographics; Variables; Taiwan; Japan; pulmonary function; FVC; asthma; obesity; BMI
• ISSN: 1178-6965; 1178-6965
• DOI: 10.2147/JAA.S299186

Asthma and obesity are important public health issues around the world. Obesity is considered a risk factor associated with the severity and incidence of asthma. We investigated the relationships between poor pulmonary function (defined by forced vital capacity (FVC) and percentage of predicted FVC (FVC%)) and obesity. This is a retrospective longitudinal study using the MJ health examination database in Taiwan from 2000 to 2015. There were 160,609 participants aged ≥20 years with complete obesity indicators and lung function data, and having at least two visits. A generalized estimation equation (GEE) model was applied to estimate the association between lung function and obesity. BMI was the best indicator to predict poor pulmonary function for our participants. Results of BMI are presented as an example: Obesity (body mass index (BMI) ≥27.0 kg/m ) is significantly associated with lower FVC [adjusted coefficients (β) for asthmatics: -0.11 L (95% CI: -0.14, -0.08); adjusted β for non-asthmatics: -0.08 L (-0.09, -0.08)] and FVC% [adjusted β for asthmatics: -1.91% (95% CI: -2.64, -1.19); adjusted β for non-asthmatics: 1.48% (-1.63, -1.33)]. Annual change of BMI (ΔBMI/year) is an independent risk factor for decreased FVC [adjusted β for asthmatics: -0.030 L (-0.048, -0.013); adjusted β for non-asthmatics: -0.019 L (-0.022, -0.016)] and FVC% [adjusted β for non-asthmatics: -0.603% (-1.063, -0.142); adjusted β for non-asthmatics: -0.304% (-0.393, -0.214)], and is significantly associated with accelerated FVC decline [adjusted β of ΔFVC/year and ΔFVC %/year for asthmatics: -0.038 L (-0.054, -0.022) and -0.873% (-1.312, -0.435); adjusted β of ΔFVC/year and ΔFVC %/year for non-asthmatics: -0.033 L (-0.042, -0.024) and -0.889% (-1.326, -0.452)]. Obesity is significantly associated with decreased lung function, and asthmatics had a higher risk than non-asthmatics.