PM10 Exposure and Non-accidental Mortality in Asian Populations: A Meta-analysis of Time-series and Case-crossover Studies

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Abstract

Objectives

We investigated the association between particulate matter less than 10 µm in aerodynamic diameter (PM ₁₀) exposure and non-accidental mortality in Asian populations by meta-analysis, using both time-series and case-crossover analysis.

Methods

Among the 819 published studies searched from PubMed and EMBASE using key words related to PM ₁₀ exposure and non-accidental mortality in Asian countries, 8 time-series and 4 case-crossover studies were selected for meta-analysis after exclusion by selection criteria. We obtained the relative risk (RR) and 95% confidence intervals (CI) of non-accidental mortality per 10 µg/m ³ increase of daily PM ₁₀ from each study. We used Q statistics to test the heterogeneity of the results among the different studies and evaluated for publication bias using Begg funnel plot and Egger test.

Results

Testing for heterogeneity showed significance ( p<0.001); thus, we applied a random-effects model. RR (95% CI) per 10 µg/m ³ increase of daily PM ₁₀ for both the time-series and case-crossover studies combined, time-series studies relative risk only, and case-crossover studies only, were 1.0047 (1.0033 to 1.0062), 1.0057 (1.0029 to 1.0086), and 1.0027 (1.0010 to 1.0043), respectively. The non-significant Egger test suggested that this analysis was not likely to have a publication bias.

Conclusions

We found a significant positive association between PM ₁₀ exposure and non-accidental mortality among Asian populations. Continued investigations are encouraged to contribute to the health impact assessment and public health management of air pollution in Asian countries.

Related collections

Most cited references 42

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Author and article information

Journal

Journal ID (nlm-ta): J Prev Med Public Health

Journal ID (iso-abbrev): J Prev Med Public Health

Journal ID (publisher-id): JPMPH

Title: Journal of Preventive Medicine and Public Health

Publisher: The Korean Society for Preventive Medicine

ISSN (Print): 1975-8375

ISSN (Electronic): 2233-4521

Publication date (Print): January 2013

Publication date (Electronic): 31 January 2013

Volume: 46

Issue: 1

Pages: 10-18

Affiliations

[1 ]Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea.

[2 ]Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul, Korea.

Author notes

Corresponding author: Yun-Chul Hong, MD, PhD. 103 Daehak-ro, Jongno-gu, Seoul 110-799, Korea. Tel: +82-2-740-8394, Fax: +82-2-747-4830, ychong1@ 123456snu.ac.kr

Article

DOI: 10.3961/jpmph.2013.46.1.10

PMC ID: 3567321

PubMed ID: 23407325

SO-VID: 29cf4932-8fda-495c-8702-cb651fa98b3a

License:

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.