Effect of outdoor air pollution on asthma exacerbations in children and adults: Systematic review and multilevel meta-analysis.

<h4>Background</h4>Several observational studies have suggested that outdoor air pollution may induce or aggravate asthma. However, epidemiological results are inconclusive due to the presence of numerous moderators which influence this association. The goal of this study was to assess t...

Full description

Saved in:
Bibliographic Details
Main Authors: Pablo Orellano, Nancy Quaranta, Julieta Reynoso, Brenda Balbi, Julia Vasquez
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:https://doi.org/10.1371/journal.pone.0174050
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849419103506268160
author Pablo Orellano
Nancy Quaranta
Julieta Reynoso
Brenda Balbi
Julia Vasquez
author_facet Pablo Orellano
Nancy Quaranta
Julieta Reynoso
Brenda Balbi
Julia Vasquez
author_sort Pablo Orellano
collection DOAJ
description <h4>Background</h4>Several observational studies have suggested that outdoor air pollution may induce or aggravate asthma. However, epidemiological results are inconclusive due to the presence of numerous moderators which influence this association. The goal of this study was to assess the relationship between outdoor air pollutants and moderate or severe asthma exacerbations in children and adults through a systematic review and multilevel meta-analysis.<h4>Material and methods</h4>We searched studies published in English on PubMed, Scopus, and Google Scholar between January 2000 and October 2016. Studies following a case-crossover design with records of emergency departments and/or hospital admissions as a surrogate of moderate or severe asthma exacerbations were selected. A multilevel meta-analysis was employed, taking into account the potential clustering effects within studies examining more than one lag. Odds ratios (ORs) and 95% confidence intervals were estimated. A subgroup analysis in children aged 0 to 18 years and a sensitivity analysis based on the quality of the included studies as defined in the Newcastle-Ottawa Scale were performed. Publication bias was evaluated through visual inspection of funnel plots and by a complementary search of grey literature. (Prospero Registration number CRD42015032323).<h4>Results</h4>Database searches retrieved 208 records, and finally 22 studies were selected for quantitative analysis. All pollutants except SO2 and PM10 showed a significant association with asthma exacerbations (NO2: 1.024; 95% CI: 1.005,1.043, SO2: 1.039; 95% CI: 0.988,1.094), PM10: 1.024; 95% CI: 0.995,1.053, PM2.5: 1.028; 95% CI: 1.009,1.047, CO: 1.045; 95% CI: 1.005,1.086, O3: 1.032; 95% CI: 1.005,1.060. In children, the association was significant for NO2, SO2 and PM2.5.<h4>Conclusion</h4>This meta-analysis provides evidence of the association between selected air pollutants and asthma exacerbations for different lags.
format Article
id doaj-art-29253a72b4cf409595cdf3bec4f52376
institution Kabale University
issn 1932-6203
language English
publishDate 2017-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj-art-29253a72b4cf409595cdf3bec4f523762025-08-20T03:32:15ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01123e017405010.1371/journal.pone.0174050Effect of outdoor air pollution on asthma exacerbations in children and adults: Systematic review and multilevel meta-analysis.Pablo OrellanoNancy QuarantaJulieta ReynosoBrenda BalbiJulia Vasquez<h4>Background</h4>Several observational studies have suggested that outdoor air pollution may induce or aggravate asthma. However, epidemiological results are inconclusive due to the presence of numerous moderators which influence this association. The goal of this study was to assess the relationship between outdoor air pollutants and moderate or severe asthma exacerbations in children and adults through a systematic review and multilevel meta-analysis.<h4>Material and methods</h4>We searched studies published in English on PubMed, Scopus, and Google Scholar between January 2000 and October 2016. Studies following a case-crossover design with records of emergency departments and/or hospital admissions as a surrogate of moderate or severe asthma exacerbations were selected. A multilevel meta-analysis was employed, taking into account the potential clustering effects within studies examining more than one lag. Odds ratios (ORs) and 95% confidence intervals were estimated. A subgroup analysis in children aged 0 to 18 years and a sensitivity analysis based on the quality of the included studies as defined in the Newcastle-Ottawa Scale were performed. Publication bias was evaluated through visual inspection of funnel plots and by a complementary search of grey literature. (Prospero Registration number CRD42015032323).<h4>Results</h4>Database searches retrieved 208 records, and finally 22 studies were selected for quantitative analysis. All pollutants except SO2 and PM10 showed a significant association with asthma exacerbations (NO2: 1.024; 95% CI: 1.005,1.043, SO2: 1.039; 95% CI: 0.988,1.094), PM10: 1.024; 95% CI: 0.995,1.053, PM2.5: 1.028; 95% CI: 1.009,1.047, CO: 1.045; 95% CI: 1.005,1.086, O3: 1.032; 95% CI: 1.005,1.060. In children, the association was significant for NO2, SO2 and PM2.5.<h4>Conclusion</h4>This meta-analysis provides evidence of the association between selected air pollutants and asthma exacerbations for different lags.https://doi.org/10.1371/journal.pone.0174050
spellingShingle Pablo Orellano
Nancy Quaranta
Julieta Reynoso
Brenda Balbi
Julia Vasquez
Effect of outdoor air pollution on asthma exacerbations in children and adults: Systematic review and multilevel meta-analysis.
PLoS ONE
title Effect of outdoor air pollution on asthma exacerbations in children and adults: Systematic review and multilevel meta-analysis.
title_full Effect of outdoor air pollution on asthma exacerbations in children and adults: Systematic review and multilevel meta-analysis.
title_fullStr Effect of outdoor air pollution on asthma exacerbations in children and adults: Systematic review and multilevel meta-analysis.
title_full_unstemmed Effect of outdoor air pollution on asthma exacerbations in children and adults: Systematic review and multilevel meta-analysis.
title_short Effect of outdoor air pollution on asthma exacerbations in children and adults: Systematic review and multilevel meta-analysis.
title_sort effect of outdoor air pollution on asthma exacerbations in children and adults systematic review and multilevel meta analysis
url https://doi.org/10.1371/journal.pone.0174050
work_keys_str_mv AT pabloorellano effectofoutdoorairpollutiononasthmaexacerbationsinchildrenandadultssystematicreviewandmultilevelmetaanalysis
AT nancyquaranta effectofoutdoorairpollutiononasthmaexacerbationsinchildrenandadultssystematicreviewandmultilevelmetaanalysis
AT julietareynoso effectofoutdoorairpollutiononasthmaexacerbationsinchildrenandadultssystematicreviewandmultilevelmetaanalysis
AT brendabalbi effectofoutdoorairpollutiononasthmaexacerbationsinchildrenandadultssystematicreviewandmultilevelmetaanalysis
AT juliavasquez effectofoutdoorairpollutiononasthmaexacerbationsinchildrenandadultssystematicreviewandmultilevelmetaanalysis