Children’s lung function improved with classroom, bedroom air purification
Key takeaways:
- FEV1, FVC, peak expiratory flow and various maximal expiratory flow measures of FVC went up with air purification.
- Fractional exhaled nitric oxide, an airway inflammation marker, went down with air purification.
In a set of healthy school-aged children, several lung function measures, including FEV1 and FVC, improved with classroom plus bedroom air purification, according to results published in JAMA Pediatrics.
“The respiratory benefits in children observed in our findings underline the importance of indoor air quality improvement to safeguard the respiratory health of children,” Haidong Kan, PhD, of the school of public health at Fudan University, the Key Lab of Public Health Safety of the Ministry of Education and the National Health Commission Key Lab of Health Technology Assessment, told Healio.
“We recommend clinicians attach importance to the hazardous impact of indoor particulate matter pollution on the respiratory system of school-age children, especially in regions with high particulate matter pollution levels,” Kan said.
In a double-blind, cluster randomized crossover trial in China, Kan and colleagues evaluated 79 healthy school-aged children (mean age, 10.3 years; age range, 10-12 years; 48% boys) to determine the benefits of 76-day classroom plus bedroom air purification on lung function, airway inflammation markers and metabolites in exhaled breath condensate vs. 76-day sham purification.
Notably, all children were exposed to true air purification and sham air purification. An 88-day washout period took place between the two interventions, according to the study.
At the assessed school site, researchers observed an outdoor PM2.5 average of 32.53 μg/m3 during the entire study period
Between the two intervention periods, a lower time-weighted personal PM2.5 concentration was found when classroom plus bedroom air purification vs. sham air purification was utilized (mean, 21.49 μg/m3 vs. 39.17 μg/m3; 45.14% decline), according to researchers.
In terms of lung function, seven measures went up with multisetting indoor air purification, signaling improvement:
- FEV1 (+8.04%; 95% CI, 2.15%-13.93%);
- peak expiratory flow (+16.52%; 95% CI, 2.76%-30.28%);
- FVC (+5.73%; 95% CI, 0.48%-10.98%);
- forced expiratory flow at 25% to 75% of FVC (+17.22%; 95% CI, 3.78%-30.67%);
- maximal expiratory flow at 75% of FVC (+14.6%; 95% CI, 0.35%-28.85%);
- maximal expiratory flow at 50% of FVC (+17.86%; 95% CI, 3.65%-32.06%); and
- maximal expiratory flow at 25% of FVC (+18.22%; 95% CI, 1.73%-34.7%).
Researchers further reported a 22.38% reduction (95% CI, 2.27%-42.48%) in the airway inflammation marker of relative fractional exhaled nitric oxide with classroom plus bedroom air purification.
When evaluating metabolites in exhaled breath condensate, air purification’s impact on respiratory measures was mediated by L-tyrosine, beta-alanine, oxypurinol and sebacic acid, according to the study. Researchers wrote that these measures included peak expiratory flow, maximal expiratory flow at 75% of FVC and fractional exhaled nitric oxide.
“Notably, based on the exceptional air purification efficiency and longer duration achieved by the multisetting air quality intervention program applied in this study, the magnitude of respiratory benefits estimated in our study surpassed those reported in previous studies involving adults and older populations,” Kan told Healio.
“Future studies may employ accurate individual exposure monitoring devices to identify the primary harmful constituents of fine particulate matter, thereby facilitating more precise prevention and control strategies for ambient particulate matter pollution,” Kan added.
For more information:
Haidong Kan, PhD, can be reached at kanh@fudan.edu.cn.