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ISA Carbon Monoxide (2010)

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1,037 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Air pollution and heart failure: Relationship with the ejection fraction

Authors: Dominguez-Rodriguez, A; Abreu-Afonso, J; Rodríguez, S; Juarez-Prera, RA; Arroyo-Ucar, E; Gonzalez, Y; Abreu-Gonzalez, P; Avanzas, P (2013) World Journal of Cardiology 5:49-53. HERO ID: 1519388

[Less] AIM: To study whether the concentrations of particulate matter in ambient air are associated . . . [More] AIM: To study whether the concentrations of particulate matter in ambient air are associated with hospital admission due to heart failure in patients with heart failure with preserved ejection fraction and reduced ejection fraction.

METHODS: We studied 353 consecutive patients admitted into a tertiary care hospital with a diagnosis of heart failure. Patients with ejection fraction of ≥ 45% were classified as having heart failure with preserved ejection fraction and those with an ejection fraction of < 45% were classified as having heart failure with reduced ejection fraction. We determined the average concentrations of different sizes of particulate matter (< 10, < 2.5, and < 1 μm) and the concentrations of gaseous pollutants (carbon monoxide, sulphur dioxide, nitrogen dioxide and ozone) from 1 d up to 7 d prior to admission.

RESULTS: The heart failure with preserved ejection fraction population was exposed to higher nitrogen dioxide concentrations compared to the heart failure with reduced ejection fraction population (12.95 ± 8.22 μg/m(3) vs 4.50 ± 2.34 μg/m(3), P < 0.0001). Multivariate analysis showed that nitrogen dioxide was a significant predictor of heart failure with preserved ejection fraction (odds ratio ranging from (1.403, 95%CI: 1.003-2.007, P = 0.04) to (1.669, 95%CI: 1.043-2.671, P = 0.03).

CONCLUSION: This study demonstrates that short-term nitrogen dioxide exposure is independently associated with admission in the heart failure with preserved ejection fraction population.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Exploring prenatal outdoor air pollution, birth outcomes and neonatal health care utilization in a nationally representative sample

Authors: Trasande, L; Wong, K; Roy, A; Savitz, DA; Thurston, G (2013) Journal of Exposure Science and Environmental Epidemiology 23:315-321. HERO ID: 1521270

[Less] The impact of air pollution on fetal growth remains controversial, in part, because studies have been . . . [More] The impact of air pollution on fetal growth remains controversial, in part, because studies have been limited to sub-regions of the United States with limited variability. No study has examined air pollution impacts on neonatal health care utilization. We performed descriptive, univariate and multivariable analyses on administrative hospital record data from 222,359 births in the 2000, 2003 and 2006 Kids Inpatient Database linked to air pollution data drawn from the US Environmental Protection Agency's Aerometric Information Retrieval System. In this study, air pollution exposure during the birth month was estimated based on birth hospital address. Although air pollutants were not individually associated with mean birth weight, a three-pollutant model controlling for hospital characteristics, demographics, and birth month identified 9.3% and 7.2% increases in odds of low birth weight and very low birth weight for each μg/m(3) increase in PM(2.5) (both P<0.0001). PM(2.5) and NO(2) were associated with -3.0% odds/p.p.m. and +2.5% odds/p.p.b. of preterm birth, respectively (both P<0.0001). A four-pollutant multivariable model indicated a 0.05 days/p.p.m. NO(2) decrease in length of the birth hospitalization (P=0.0061) and a 0.13 days increase/p.p.m. CO (P=0.0416). A $1166 increase in per child costs was estimated for the birth hospitalization per p.p.m. CO (P=0.0002) and $964 per unit increase in O(3) (P=0.0448). A reduction from the 75th to the 25th percentile in the highest CO quartile for births predicts annual savings of $134.7 million in direct health care costs. In a national, predominantly urban, sample, air pollutant exposures during the month of birth are associated with increased low birth weight and neonatal health care utilization. Further study of this database, with enhanced control for confounding, improved exposure assessment, examination of exposures across multiple time windows in pregnancy, and in the entire national sample, is supported by these initial investigations.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Time-series analyses of air pollution and mortality in the United States: A subsampling approach

Authors: Moolgavkar, SH; Mcclellan, RO; Dewanji, A; Turim, J; Luebeck, EG; Edwards, M (2013) Environmental Health Perspectives 121:73-78. HERO ID: 1419410

[Less] BACKGROUND: Hierarchical Bayesian methods have been used in previous papers to estimate national mean . . . [More] BACKGROUND: Hierarchical Bayesian methods have been used in previous papers to estimate national mean effects of air pollutants on daily deaths in time-series analyses. OBJECTIVES: To obtain maximum likelihood estimates of the common national effects of the criteria pollutants on mortality based on time-series data from up to 108 metropolitan areas in the U.S. METHODS: We used a subsampling bootstrap procedure to obtain the maximum likelihood estimates and confidence bounds for common national effects of the criteria pollutants, as measured by the percentage increase in daily mortality associated with a unit increase in daily 24-hour mean pollutant concentration on the previous day, while controlling weather and temporal trends. Five pollutants, PM10, ozone, CO, NO2, and SO2 were considered in single and multi-pollutant analyses. Flexible ambient concentration-response models for the pollutant effects were considered as well. Limited sensitivity analyses with different degrees of freedom for time trends were performed. RESULTS: In single pollutant models, we observed significant associations of daily deaths with all pollutants. The ozone coefficient was highly sensitive to the degree of smoothing of time trends. Among the gases, SO2 and NO2 were most strongly associated with mortality. The flexible ambient concentration-response curve for ozone showed evidence of non-linearity and a threshold at about 30 ppb. CONCLUSIONS: Differences between the results of our analyses and those reported from the Bayesian approach suggest that estimates of the quantitative impact of pollutants are dependent on choice of statistical approach, although results are not directly comparable because they are based on different data. Additionally, the estimate of the ozone-mortality coefficient depends on the amount of smoothing of time trends.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

The association of ambient air pollution and traffic exposures with selected congenital anomalies in the San Joaquin Valley of California

Authors: Padula, AM; Tager, IB; Carmichael, SL; Hammond, SK; Lurmann, F; Shaw, GM (2013) American Journal of Epidemiology 177:1074-1085. HERO ID: 1518997

[Less] Congenital anomalies are a leading cause of infant mortality and are important contributors to subsequent . . . [More] Congenital anomalies are a leading cause of infant mortality and are important contributors to subsequent morbidity. Studies suggest associations between environmental contaminants and some anomalies, although evidence is limited. We aimed to investigate whether ambient air pollutant and traffic exposures in early gestation contribute to the risk of selected congenital anomalies in the San Joaquin Valley of California, 1997-2006. Seven exposures and 5 outcomes were included for a total of 35 investigated associations. We observed increased odds of neural tube defects when comparing the highest with the lowest quartile of exposure for several pollutants after adjusting for maternal race/ethnicity, education, and multivitamin use. The adjusted odds ratio for neural tube defects among those with the highest carbon monoxide exposure was 1.9 (95% confidence interval: 1.1, 3.2) compared with those with the lowest exposure, and there was a monotonic exposure-response across quartiles. The highest quartile of nitrogen oxide exposure was associated with neural tube defects (adjusted odds ratio = 1.8, 95% confidence interval: 1.1, 2.8). The adjusted odds ratio for the highest quartile of nitrogen dioxide exposure was 1.7 (95% confidence interval: 1.1, 2.7). Ozone was associated with decreased odds of neural tube defects and increased odds of gastroschisis among mothers aged ≥20 years. Our results extend the limited body of evidence regarding air pollution exposure and adverse birth outcomes.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Association between changes in air pollution levels during the Beijing Olympics and biomarkers of inflammation and thrombosis in healthy young adults

Authors: Rich, DQ; Kipen, HM; Huang, W; Wang, G; Wang, Y; Zhu, P; Ohman-Strickland, P; Hu, M; Philipp, C; Diehl, SR; Lu, SE; Tong, J; Gong, J; Thomas, D; Zhu, T; Zhang, JJ (2012) JAMA: Journal of the American Medical Association 307:2068-2078. HERO ID: 1257762

[Less] CONTEXT: Air pollution is a risk factor for cardiovascular diseases (CVD), but the . . . [More] CONTEXT: Air pollution is a risk factor for cardiovascular diseases (CVD), but the underlying biological mechanisms are not well understood.

OBJECTIVE: To determine whether markers related to CVD pathophysiological pathways (biomarkers for systemic inflammation and thrombosis, heart rate, and blood pressure) are sensitive to changes in air pollution.

DESIGN, SETTING, AND PARTICIPANTS: Using a quasi-experimental opportunity offered by greatly restricted air pollution emissions during the Beijing Olympics, we measured pollutants daily and the outcomes listed below in 125 healthy young adults before, during, and after the 2008 Olympics (June 2-October 30). We used linear mixed-effects models to estimate the improvement in outcome levels during the Olympics and the anticipated reversal of outcome levels after pollution controls ended to determine whether changes in outcome levels were associated with changes in pollutant concentrations.

MAIN OUTCOME MEASURES: C-reactive protein (CRP), fibrinogen, von Willebrand factor, soluble CD40 ligand (sCD40L), soluble P-selectin (sCD62P) concentrations; white blood cell count (WBC); heart rate; and blood pressure.

RESULTS: Concentrations of particulate and gaseous pollutants decreased substantially (-13% to -60%) from the pre-Olympic period to the during-Olympic period. Using 2-sided tests conducted at the .003 level, we observed statistically significant improvements in sCD62P levels by -34.0% (95% CI, -38.4% to -29.2%; P < .001) from a pre-Olympic mean of 6.29 ng/mL to a during-Olympic mean of 4.16 ng/mL and von Willebrand factor by -13.1% (95% CI, -18.6% to -7.5%; P < .001) from 106.4% to 92.6%. After adjustments for multiple comparisons, changes in the other outcomes were not statistically significant. In the post-Olympic period when pollutant concentrations increased, most outcomes approximated pre-Olympic levels, but only sCD62P and systolic blood pressure were significantly worsened from the during-Olympic period. The fraction of above-detection-limit values for CRP (percentage ≥ 0.3 mg/L) was reduced from 55% in the pre-Olympic period to 46% in the during-Olympic period and reduced further to 36% in the post-Olympic period. Interquartile range increases in pollutant concentrations were consistently associated with statistically significant increases in fibrinogen, von Willebrand factor, heart rate, sCD62P, and sCD40L concentrations.

CONCLUSIONS: Changes in air pollution levels during the Beijing Olympics were associated with acute changes in biomarkers of inflammation and thrombosis and measures of cardiovascular physiology in healthy young persons. These findings are of uncertain clinical significance.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Susceptibility to air pollution effects on mortality in Seoul, Korea: A case-crossover analysis of individual-level effect modifiers

Authors: Son, JY; Lee, JT; Kim, H; Yi, O; Bell, ML (2012) Journal of Exposure Science and Environmental Epidemiology 22:227-234. HERO ID: 1034976

[Less] Air pollution's mortality effects may differ by subpopulation; however, few studies have investigated . . . [More] Air pollution's mortality effects may differ by subpopulation; however, few studies have investigated this issue in Asia. We investigated susceptibility to air pollutants on total, cardiovascular, and respiratory mortality in Seoul, Korea for the period 2000-2007. We applied time-stratified case-crossover analysis, which allows direct modeling of interaction terms, to estimate susceptibility based on sex, age, education, marital status, and occupation. An interquartile range increase in pollution was associated with odds ratios of 0.94 (95% confidence interval, 0.25-1.62), 2.27 (1.03-3.53), 1.94 (0.80-3.09), and 2.21 (1.00-3.43) for total mortality and 1.95 (0.64-3.27), 4.82 (2.18-7.54), 3.64 (1.46-5.87), and 4.32 (1.77-6.92) for cardiovascular mortality for PM(10), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), and carbon monoxide (CO), respectively. Ozone effect estimates were positive, but not statistically significant. Results indicate that some populations are more susceptible than others. For total or cardiovascular mortality, associations were higher for males, those 65-74 years, and those with no education or manual occupation for some pollutants. For example, the odds ratio for SO(2) and cardiovascular mortality was 1.19 (1.03-1.37) times higher for those with manual occupations than professional occupations. Our findings provide evidence that some populations are more susceptible to the effects of air pollution than others, which has implications for public policy and risk assessment for susceptible subpopulations.Journal of Exposure Science and Environmental Epidemiology advance online publication, 7 March 2012;  doi:10.1038/jes.2012.6.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Short-term effects of air pollution on pulse pressure among nonsmoking adults

Authors: Chen, SY; Su, TC; Lin, YL; Chan, CC (2012) Epidemiology 23:341-348. HERO ID: 1256404

[Less] BACKGROUND: Previous studies on the effects of acute air pollution have focused primarily . . . [More] BACKGROUND: Previous studies on the effects of acute air pollution have focused primarily on blood pressure (BP).

METHODS: Our study enrolled 9238 nonsmoking adults over 30 years of age from 6 townships in Taiwan: 1 seaport, 1 urban, 1 industrial, and 3 rural. Using generalized additive models, we evaluated the associations between brachial BP and short-term exposure to 5 air pollutants: particulate matter with diameter <10 μm (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxide (NO(2)), carbon monoxide (CO), and ozone (O(3)).

RESULTS: After adjusting for individual and meteorologic factors, the systolic BP was decreased by all 5 pollutants, whereas the diastolic BP was increased by SO(2), NO(2), and O(3). The pulse pressure was consistently decreased by all 5 pollutants, with changes of -1.5 (95% confidence interval = -2.0 to -1.1), -0.6 (-0.9 to -0.4), -2.4 (-3.0 to -1.8), -1.2 (-1.6 to -0.9), and -1.4 (-1.8 to -0.9) mm Hg for interquartile range increases in 3-day lagged PM(10), SO(2), NO(2), carbon monoxide, and O(3), respectively. PM(10) exposure was more strongly associated with reduction of pulse pressure among men, persons >60 years of age, those with hypertension, and those living in the industrial township.

CONCLUSIONS: Short-term exposure to air pollution reduces pulse pressure. PM(10) in industrial emissions may contribute to pulse pressure changes. Age, sex, and hypertensive status may modify the effects of PM(10) on pulse pressure.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Apparent temperature and acute myocardial infarction hospital admissions in Copenhagen, Denmark: A case-crossover study

Authors: Wichmann, J; Ketzel, M; Ellermann, T; Loft, S (2012) Environmental Health: A Global Access Science Source 11. HERO ID: 1255122

[Less] BACKGROUND: The influence of temperature on acute myocardial infarction (AMI) has not . . . [More] BACKGROUND: The influence of temperature on acute myocardial infarction (AMI) has not been investigated as extensively as the effects of broader outcomes of morbidity and mortality. Sixteen studies reported inconsistent results and two considered confounding by air pollution. We addressed some of the methodological limitations of the previous studies in this study.

METHODS: This is the first study of the association between the daily 3-hour maximum apparent temperature (Tapp(max)) and AMI hospital admissions in Copenhagen. The study period covered 1 January 1999-31 December 2006, stratified in warm (April-September) and cold (October-March) periods. A case-crossover epidemiology study design was applied. Models were adjusted for public holidays and influenza, confounding by PM₁₀, NO₂ and CO was investigated, the lag and non-linear effects of Tapp(max) was examined, effect modification by age, sex and SES was explored, and the results of the case-crossover models were compared to those of the generalised additive Poisson time-series and generalised estimating equation models.

RESULTS: 14,456 AMI hospital admissions (12,995 people) occurred during the study period. For an inter-quartile range (6 or 7°C) increase in the 5-day cumulative average of Tapp(max), a 4% (95% CI:-2%; 10%) and 9% (95% CI: 3%; 14%) decrease in the AMI admission rate was observed in the warm and cold periods, respectively. The 19-65 year old group, men and highest SES group seemed to be more susceptible in the cold period.

CONCLUSION: An increase in Tapp(max) is associated with a decrease in AMI admissions during the colder months.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Main air pollutants and myocardial infarction: A systematic review and meta-analysis

Authors: Mustafic, H; Jabre, P; Caussin, C; Murad, MH; Escolano, S; Tafflet, M; Périer, MC; Marijon, E; Vernerey, D; Empana, JP; Jouven, X (2012) JAMA: Journal of the American Medical Association 307:713-721. [Review] HERO ID: 1050662

[Less] CONTEXT: Short-term exposure to high levels of air pollution may trigger myocardial . . . [More] CONTEXT: Short-term exposure to high levels of air pollution may trigger myocardial infarction (MI), but this association remains unclear.

OBJECTIVE: To assess and quantify the association between short-term exposure to major air pollutants (ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter ≤10 μm [PM(10)] and ≤2.5 μm [PM(2.5)] in diameter) on MI risk.

DATA SOURCES: EMBASE, Ovid MEDLINE in-process and other nonindexed citations, and Ovid MEDLINE (between 1948 and November 28, 2011), and EBM Reviews-Cochrane Central Register of Controlled Trials and EBM Reviews-Cochrane Database of Systematic Reviews (between 2005 and November 28, 2011) were searched for a combination of keywords related to the type of exposure (air pollution, ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, PM(10), and PM(2.5)) and to the type of outcome (MI, heart attack, acute coronary syndrome).

STUDY SELECTION: Two independent reviewers selected studies of any study design and in any language, using original data and investigating the association between short-term exposure (for up to 7 days) to 1 or more air pollutants and subsequent MI risk. Selection was performed from abstracts and titles and pursued by reviewing the full text of potentially eligible studies.

DATA EXTRACTION: Descriptive and quantitative information was extracted from each selected study. Using a random effects model, relative risks (RRs) and 95% CIs were calculated for each increment of 10 μg/m(3) in pollutant concentration, with the exception of carbon monoxide, for which an increase of 1 mg/m(3) was considered.

DATA SYNTHESIS: After a detailed screening of 117 studies, 34 studies were identified. All the main air pollutants, with the exception of ozone, were significantly associated with an increase in MI risk (carbon monoxide: 1.048; 95% CI, 1.026-1.070; nitrogen dioxide: 1.011; 95% CI, 1.006-1.016; sulfur dioxide: 1.010; 95% CI, 1.003-1.017; PM(10): 1.006; 95% CI, 1.002-1.009; and PM(2.5): 1.025; 95% CI, 1.015-1.036). For ozone, the RR was 1.003 (95% CI, 0.997-1.010; P = .36). Subgroup analyses provided results comparable with those of the overall analyses. Population attributable fractions ranged between 0.6% and 4.5%, depending on the air pollutant.

CONCLUSION: All the main air pollutants, with the exception of ozone, were significantly associated with a near-term increase in MI risk.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Air pollution and emergency department visits for asthma in Windsor, Canada

Authors: Lavigne, E; Villeneuve, PJ; Cakmak, S (2012) Canadian Journal of Public Health 103:4-8. HERO ID: 1240059

[Less] OBJECTIVES: The city of Windsor is recognized to have poor air quality in comparison . . . [More] OBJECTIVES: The city of Windsor is recognized to have poor air quality in comparison with other Canadian cities. However, relatively few studies have evaluated associations between day-to-day fluctuations in air pollution levels and respiratory health in Windsor. In this study, we examined associations between short-term changes in ambient air pollution and emergency department (ED) visits for asthma in Windsor.

METHODS: A time-stratified case-crossover design was applied to 3,728 ED visits for asthma that occurred in Windsor area hospitals between 2002 and 2009. Daily air pollution levels for the region were estimated using Environment Canada's network of fixed-site monitors. ED visits were identified through the National Ambulatory Care Reporting System (NACRS). Odds ratios and their corresponding 95% confidence intervals were estimated using conditional logistic regression, and were adjusted for the confounding influence of daily number of influenza ED visits and weather variables using natural spline functions.

RESULTS: Statistically significant associations were observed between ambient air pollution levels and ED visits for asthma in Windsor. Effects were particularly pronounced among children 2 to 14 years of age between April and September. Namely, increases in the interquartile range with 1-day lagged exposure to SO2, NO2 and CO levels were associated with increased risks of an asthma visit of 19%, 25% and 36%, respectively.

CONCLUSION: Exposure in Windsor to ambient air pollution increases the risk of ED visits for asthma, particularly among children.