Effect of Acute PM2.5 Exposure on Lung Function in Children: A Systematic Review and Meta-Analysis

Abstract

Objective

The objective of this study was to conduct a systematic review and meta-analysis to identify the adverse effects of acute PM2.5 exposure on lung function in children.

Design

Systematic review and meta-analysis. Setting, participants and measures: Eligible studies analyzing PM2.5 level and lung function in children were screened out. Effect estimates of PM2.5 measurements were quantified using random effect models. Heterogeneity was investigated with Q-test and I² statistics. We also conducted meta-regression and sensitivity analysis to explore the sources of heterogeneity, such as different countries and asthmatic status. Subgroup analyses were conducted to determine the effects of acute PM2.5 exposure on children of different asthmatic status and in different countries.

Results

A total of 11 studies with 4314 participants from Brazil, China and Japan were included finally. A 10 μg/m³ increase of PM2.5 was associated with a 1.74L/min (95% CI: −2.68, −0.90) decrease in peak expiratory flow (PEF). Since the asthmatic status and country could partly explain the heterogeneity, we conducted the subgroup analysis. Children with severe asthma were more susceptible to PM2.5 exposure (−3.11 L/min per 10 μg/m³ increase, 95% CI −4.54, −1.67) than healthy children (−1.61 L/min per 10 μg/m³ increase, 95% CI −2.34, −0.91). In the children of China, PEF decreased by 1.54 L/min (95% CI −2.33, −0.75) with a 10 μg/m³ increase in PM2.5 exposure. In the children of Japan, PEF decreased by 2.65 L/min (95% CI −3.82, −1.48) with a 10 μg/m³ increase of PM2.5 exposure. In contrast, no statistic association was found between every 10 μg/m³ increase of PM2.5 and lung function in children of Brazil (−0.38 L/min, 95% CI −0.91, 0.15).

Conclusion

Our results demonstrated that the acute PM2.5 exposure exerted adverse impacts on children’s lung function, and children with severe asthma were more susceptible to the increase of PM2.5 exposure. The impacts of acute PM2.5 exposure varied across different countries.

Keywords:

• particulate matter 2.5
• PM2.5
• children
• peak expiratory flow
• PEF
• acute exposure
• meta-analysis

Abbreviations

CI, 95% confidence interval; PM2.5, particulate matter 2.5; PEF, peak expiratory flow; FVC, forced vital capacity; FEV1, forced expiratory volume in 1 s; PAHs, polycyclic aromatic hydrocarbons; COPD, chronic obstructive pulmonary disease; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta Analyses; NOS, Newcastle-Ottawa Scale; NOS2, Nitric Oxide Synthase 2; SIRT1, Sirtuin 1.

Data Sharing Statement

All data used in this meta-analysis are freely and publicly available from the cited papers used in the analysis; the full citations are in the reference list.

Ethics Approval and Consent to Participate

Not applicable here, as this is a systematic review and meta-analysis.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

The authors declare that there are no competing interests.

Additional information

Funding

No funding was received for this study.