Influence of exposure differences on city-to-city heterogeneity in PM2.5-mortality associations in US cities

Baxter, LK; Crooks, JL; Sacks, JD

HERO ID

3453687

Reference Type

Journal Article

Year

2017

Language

English

PMID

28049482

HERO ID 3453687
In Press No
Year 2017
Title Influence of exposure differences on city-to-city heterogeneity in PM2.5-mortality associations in US cities
Authors Baxter, LK; Crooks, JL; Sacks, JD
Journal Environmental Health
Volume 16
Issue 1
Page Numbers 1
Abstract <strong>BACKGROUND: </strong>Multi-city population-based epidemiological studies have observed heterogeneity between city-specific fine particulate matter (PM2.5)-mortality effect estimates. These studies typically use ambient monitoring data as a surrogate for exposure leading to potential exposure misclassification. The level of exposure misclassification can differ by city affecting the observed health effect estimate.<br /><br /><strong>METHODS: </strong>The objective of this analysis is to evaluate whether previously developed residential infiltration-based city clusters can explain city-to-city heterogeneity in PM2.5 mortality risk estimates. In a prior paper 94 cities were clustered based on residential infiltration factors (e.g. home age/size, prevalence of air conditioning (AC)), resulting in 5 clusters. For this analysis, the association between PM2.5 and all-cause mortality was first determined in 77 cities across the United States for 2001-2005. Next, a second stage analysis was conducted evaluating the influence of cluster assignment on heterogeneity in the risk estimates.<br /><br /><strong>RESULTS: </strong>Associations between a 2-day (lag 0-1 days) moving average of PM2.5 concentrations and non-accidental mortality were determined for each city. Estimated effects ranged from -3.2 to 5.1% with a pooled estimate of 0.33% (95% CI: 0.13, 0.53) increase in mortality per 10 μg/m(3) increase in PM2.5. The second stage analysis determined that cluster assignment was marginally significant in explaining the city-to-city heterogeneity. The health effects estimates in cities with older, smaller homes with less AC (Cluster 1) and cities with newer, smaller homes with a large prevalence of AC (Cluster 3) were significantly lower than the cluster consisting of cities with older, larger homes with a small percentage of AC.<br /><br /><strong>CONCLUSIONS: </strong>This is the first study that attempted to examine whether multiple exposure factors could explain the heterogeneity in PM2.5-mortality associations. The results of this study were found to explain a small portion (6%) of this heterogeneity.
Doi 10.1186/s12940-016-0208-y
Pmid 28049482
Wosid WOS:000391752400001
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Is Peer Review Yes