Associations of personal exposure to air pollutants with airway mechanics in children with asthma. (May 2020)

• Record Type: Journal Article
• Authors: He, Linchen; Li, Zhen; Teng, Yanbo; Cui, Xiaoxing; Barkjohn, Karoline K.; Norris, Christina; Fang, Lin; Lin, Lili; Wang, Qian; Zhou, Xiaojian; Hong, Jianguo; Li, Feng; Zhang, Yinping; Schauer, James J.; Black, Marilyn; Bergin, Michael H.; Zhang, Junfeng (Jim)
• Is Part Of: Environment international. Volume 138(2020)
• Publication Date: 2020-05
• Subjects: PM2.5 particles with an aerodynamic diameter ≤ 2.5μm -- O3 ozone -- IOS impulse oscillometry -- HEPA high-efficiency particulate air -- I/O ratio indoor/outdoor -- IgE immunoglobulin E -- Z5 airway impedence measured at 5Hz -- R5 airway resistance measured at 5Hz -- R20 airway resistance measured at 20Hz -- R5-R20 difference between airway resistance measured at 5Hz and 20Hz -- X5 airway reactance measured at 5Hz -- Fres resonant frequency -- FEV1 forced expiratory volume in first second -- FEV1/FEV1 predicted the ratio between FEV1 and predicted FEV1 -- FVC forced vital capacity -- FVC/FVC predicted: the ratio between FVC and predicted FVC -- PEF peak expiratory flow -- FEF25-75 the average forced expiratory flow during 25% to 75% of FVC -- FEV1/FVC the ratio between FEV1 and FVC -- FeNO fractional exhaled nitric oxide -- LMER linear mixed-effects regression -- VOCs volatile organic compounds -- SVOCs semi-volatile organic compounds; Airway mechanics -- Asthmatic children -- Air pollution exposure -- Pulmonary physiology -- Asthma management -- Impulse oscillometry; Environmental protection -- Periodicals; Environmental health -- Periodicals; Environmental monitoring -- Periodicals; Environmental Monitoring -- Periodicals; Environnement -- Protection -- Périodiques; Hygiène du milieu -- Périodiques; Environnement -- Surveillance -- Périodiques; Environmental health; Environmental monitoring; Environmental protection; Periodicals; 333.705
• DOI: 10.1016/j.envint.2020.105647
• Languages: English
• ISSNs: 0160-4120

Abstract

Highlights: Airway mechanics could indicate subtle changes in pulmonary physiology. Exposure to PM2.5 was associated with changes in airway resistance and inflammation. It is important to reduce personal PM2.5 exposure in personalized asthma management. Abstract: Background: The importance of airway mechanics has been increasingly recognized in pediatric asthma. However, no studies have examined responses of airway mechanics to air pollution exposure in asthmatic children. Methods: In this panel study involving indoor air filtration manipulation that created a large gradient of personal exposure to PM2.5, the airway mechanics and lung function of 43 asthmatic children 5–13 years old in a suburb of Shanghai were measured four times within 3 consecutive months. Concentrations of indoor and outdoor PM2.5 and ozone were coupled with individual time-activity data to calculate personal exposures. Linear mixed effects models were used to examine the relationships of personal exposure with indicators of airway mechanics and lung function, respectively. Results: An interquartile range (IQR) increase in 24-hour average PM2.5 personal exposure (30.3 µg/m 3 ) in the prior day was associated with significant increases in small airway resistance (R5 -R20 ) of 15.8%, total airway resistance (R5 ) of 6.3%, and airway inflammation (FeNO) of 9.6%. These associations were stronger in children with lower blood eosinophil counts (<450/µL). No significant associations were found between personal PM2.5 exposure and lung function. Low-level ozone exposure (daily maximum 8-hour exposure range 1.1–56.4 ppb) was not significantly associated with any of the outcomes. Conclusion: Changes in personal PM2.5 exposure, partly enhanced by air filtration, were associated with significant changes in airway resistance and inflammation in children with asthma. These findings suggest the importance of reducing PM2.5 exposure, via personal air quality management, in improving airflow limitation in the airways, especially the small airways.