Evidence map›Paper›PMID 23842601›Full record

ArticleEnvironmental health perspectives2013

Ambient ozone concentrations and the risk of perforated and nonperforated appendicitis: a multicity case-crossover study.

Gilaad G Kaplan, Divine Tanyingoh, Elijah Dixon, Markey Johnson, Amanda J Wheeler, Robert P Myers, Stefania Bertazzon, Vineet Saini, Karen Madsen, Subrata Ghosh and 1 more

Abstract readMulticenter Study
In one paragraph

Article in Environmental health perspectives, 2013. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers.

0numbers the graph read from it
0cells of the map it votes in
21citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

21 citing papers in PubMed.

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  17. Role of environmental pollution in irritable bowel syndrome.World journal of gastroenterology · 2015
    Review
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

11 authors.

Gilaad G KaplanDepartment of Medicine, Environmental Health Research Group, Institute of Public Health, University of Calgary, Calgary, Alberta, Canada. ggkaplan@ucalgary.ca
Divine Tanyingoh
Elijah Dixon
Markey Johnson
Amanda J Wheeler
Robert P Myers
Stefania Bertazzon
Vineet Saini
Karen Madsen
Subrata Ghosh
Paul J Villeneuve

Funding

Canadian Institutes of Health Research
6 · The paper itself

Abstract

backgroundEnvironmental determinants of appendicitis are poorly understood. Past work suggests that air pollution may increase the risk of appendicitis.

objectivesWe investigated whether ambient ground-level ozone (O3) concentrations were associated with appendicitis and whether these associations varied between perforated and nonperforated appendicitis.

methodsWe based this time-stratified case-crossover study on 35,811 patients hospitalized with appendicitis from 2004 to 2008 in 12 Canadian cities. Data from a national network of fixed-site monitors were used to calculate daily maximum O3 concentrations for each city. Conditional logistic regression was used to estimate city-specific odds ratios (ORs) relative to an interquartile range (IQR) increase in O3 adjusted for temperature and relative humidity. A random-effects meta-analysis was used to derive a pooled risk estimate. Stratified analyses were used to estimate associations separately for perforated and nonperforated appendicitis.

resultsOverall, a 16-ppb increase in the 7-day cumulative average daily maximum O3 concentration was associated with all appendicitis cases across the 12 cities (pooled OR = 1.07; 95% CI: 1.02, 1.13). The association was stronger among patients presenting with perforated appendicitis for the 7-day average (pooled OR = 1.22; 95% CI: 1.09, 1.36) when compared with the corresponding estimate for nonperforated appendicitis [7-day average (pooled OR = 1.02, 95% CI: 0.95, 1.09)]. Heterogeneity was not statistically significant across cities for either perforated or nonperforated appendicitis (p > 0.20).

conclusionsHigher levels of ambient O3 exposure may increase the risk of perforated appendicitis.

Indexed as

Environmental ExposureAdultAir PollutantsAppendicitisCanadaCitiesCross-Over StudiesEnvironmental MonitoringFemaleHumansIncidenceMaleMiddle AgedOzoneRetrospective StudiesSeasonsAir PollutantsOzone

Identifiers

PMID23842601
PMCPMC3734492

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.