Examining associations between childhood asthma and traffic flow using a geographic information system (original) (raw)
Related papers
International Journal of Environmental Research and Public Health
Asthma in children poses a significant clinical and public health burden. We examined the association between reported neighborhood traffic (a proxy for traffic-related air pollution) and asthma among 855 multi-racial children aged 4–8 years old who participated in the Environmental Influences on Child Health Outcomes (ECHO) cohort. We hypothesized that high neighborhood traffic density would be associated with the prevalence of asthma. Asthma/asthma-like symptoms (defined as current and/or past physician diagnosed asthma, past wheezing, or nighttime cough or wheezing in the past 12 months) was assessed by parental report. The relationship between neighborhood traffic and asthma/asthma-like symptoms was assessed using logistic regression. The prevalence of asthma/asthma-like symptoms among study participants was 23%, and 15% had high neighborhood traffic. Children with significant neighborhood traffic had a higher odds of having asthma/asthma-like symptoms than children without neig...
International Journal of Health Geographics, 2009
Background: There is increasing evidence that residential proximity to roadways is associated with an elevated risk of asthma exacerbation. However, there is no consensus on the distance at which these health effects diminishes to background levels. Therefore the optimal, clinically relevant measure of exposure remains uncertain. Using four spatially defined exposure metrics, we evaluated the association between residential proximity to roadways and emergency department (ED) presentation for asthma in Perth, Western Australia.
Childhood Asthma Hospitalization and Residential Exposure to State Route Traffic
Environmental Research, 2002
This study investigated whether pediatric hospitalization for asthma was related to living near a road with heavy trafAc. In this case+control study, cases (N ؍ 417) consisted of white children aged 0+14 years who were admitted for asthma and who resided in Erie County, New York, excluding the city of Buffalo. Controls (N ؍ 461) were children in the same age range admitted during the same time period for nonrespiratory diseases. Subjects' residential addresses were linked to trafAc information provided by the New York State Department of Transportation. After adjustments for age and poverty level were made, children hospitalized for asthma were more likely to live on roads with the highest tertile of vehicle miles traveled (VMT) (odds ratio (OR): 1.93, 95% conAdence interval (CI): 1.13+3.29) within 200 m and were more likely to have trucks and trailers passing by within 200 m of their residence (OR ؍ 1.43, 95% CI: 1.03+1.99) compared to controls. However, childhood asthma hospitalization was not signiAcantly associated with residential distance from state roads, annual VMT within 500 m, or whether trucks or trailers passed by within 500 m. This study suggests that exposure to high volumes of trafAc/trucks within 200 m of homes contributes to childhood asthma hospitalizations.
Environmental Health, 2011
Background This study had two principal objectives: (i) to investigate the relationship between asthma severity and proximity to major roadways in Perth, Western Australia; (ii) to demonstrate a more accurate method of exposure assessment for traffic pollutants using an innovative GIS-based measure that fully integrates all traffic densities around subject residences. Methods We conducted a spatial case-control study, in which 'cases' were defined as individuals aged under 19 years of age with more severe asthma (defined here as two or more emergency department contacts with asthma in a defined 5-year period) versus age- and gender-matched 'controls' with less severe asthma (defined here as one emergency department contact for asthma). Traffic exposures were measured using a GIS-based approach to determine the lengths of the roads falling within a buffer area, and then multiplying them by their respective traffic counts. Results We examined the spatial relationship between emergency department contacts for asthma at three different buffer sizes: 50 metres, 100 metres and 150 metres. No effect was noted for the 50 metre buffer (OR = 1.07; 95% CI: 0.91-1.26), but elevated odds ratios were observed with for crude (unadjusted) estimates OR = 1.21 (95% CI: 1.00-1.46) for 100 metre buffers and OR = 1.25 (95% CI: 1.02-1.54) for 150 metre buffers. For adjusted risk estimates, only the 150 metre buffer yielded a statistically significant finding (OR = 1.24; 95% CI:1.00-1.52). Conclusions Our study revealed a significant 24% increase in the risk of experiencing multiple emergency department contacts for asthma for every log-unit of traffic exposure. This study provides support for the hypothesis that traffic related air pollution increases the frequency of health service contacts for asthma. This study used advanced GIS techniques to establish traffic-weighted buffer zones around the geocoded residential location of subjects to provide an accurate assessment of exposure to traffic emissions, thereby providing a quantification of the ranges over which pollutants may exert a health effect.
2011
Background: The relationship between asthma and traffic-related pollutants has received considerable attention. The use of individual-level exposure measures, such as residence location or proximity to emission sources, may avoid ecological biases. Method: This study focused on the pediatric Medicaid population in Detroit, MI, a high-risk population for asthmarelated events. A population-based matched case-control analysis was used to investigate associations between acute asthma outcomes and proximity of residence to major roads, including freeways. Asthma cases were identified as all children who made at least one asthma claim, including inpatient and emergency department visits, during the three-year study period, 2004-06. Individually matched controls were randomly selected from the rest of the Medicaid population on the basis of non-respiratory related illness. We used conditional logistic regression with distance as both categorical and continuous variables, and examined non-linear relationships with distance using polynomial splines. The conditional logistic regression models were then extended by considering multiple asthma states (based on the frequency of acute asthma outcomes) using polychotomous conditional logistic regression. Results: Asthma events were associated with proximity to primary roads with an odds ratio of 0.97 (95% CI: 0.94, 0.99) for a 1 km increase in distance using conditional logistic regression, implying that asthma events are less likely as the distance between the residence and a primary road increases. Similar relationships and effect sizes were found using polychotomous conditional logistic regression. Another plausible exposure metric, a reduced form response surface model that represents atmospheric dispersion of pollutants from roads, was not associated under that exposure model. Conclusions: There is moderately strong evidence of elevated risk of asthma close to major roads based on the results obtained in this population-based matched case-control study.
Residential Proximity to a Major Roadway Is Associated with Features of Asthma Control in Children
PLoS ONE, 2012
While several studies suggest that traffic-related air pollutants are detrimental for respiratory health, few studies have examined relationships between residential proximity to a major roadway and asthma control in children. Furthermore, a major limitation of existing research is reliance on self-reported outcomes. We therefore determined the spatial relationship between the distance from a major roadway and clinical, physiologic and inflammatory features of asthma in a highly characterized sample of asthmatic children 6-17 years of age across a wide range of severities. We hypothesized that a closer residential proximity to a major roadway would be associated with increased respiratory symptoms, altered pulmonary function and a greater magnitude of airway and systemic inflammation.
Journal of Allergy, 2010
Background. Proximity to heavy traffic has been linked to increased asthma severity. However, it is unknown whether exposure to heavy traffic is associated with the ability to maintain asthma control. Objectives. This study examines whether exposure to heavy traffic is associated with the ability to maintain asthma control in inner-city children. Methods. 756 inner-city asthmatic Hispanic children were followed for one year in a pediatric asthma management program (Breathmobile). At each scheduled visit, asthma specialist tracked patients' asthma severity and managed their asthma based on the NAEPP guidelines. The patients' residential distance from the nearest freeway was calculated based on residential address at study entry. Distance to nearest freeway was used as a surrogate marker for high exposure from traffic-related air pollutants. Results. Patients who lived near a freeway were significantly more likely to have asthma that was not well controlled (P = .03). Patients with intermittent and mild baseline severity have a twofold increased risk of having asthma that is uncontrolled if they lived < 2 miles from a freeway (OR = 2.2, P = .04). Conclusion. In children with asthma, residential proximity to freeways is associated with uncontrolled asthma.
2020
Background Asthma exacerbations in children often require medications, urgent care, and hospitalization. Multiple environmental triggers have been associated with asthma exacerbations, including particulate matter 2.5 (PM2.5) and carbon monoxide (CO), which are primarily generated by motor vehicle exhaust. There is mixed evidence as to whether proximity to highways increases risk of asthma exacerbations. Methods To test this hypothesis, we assessed the association between asthma exacerbations and the distance to two types of roadways in Durham County, accounting for other patient-level factors. We abstracted data from the Duke University Health System electronic health record (EHR), identifying 6,208 children with asthma between 2014 – 2019. We geocoded each child’s distance to roadways (both 35 MPH+ and 55 MPH+). We classified asthma exacerbation severity into four tiers and fitted a recurrent event survival model to account for multiple exacerbations. Results There was a consisten...
The influence of neighborhood traffic density on the respiratory health of elementary schoolchildren
Environment International, 2012
Background: Several studies have found that living near major roadways is associated with an increase in respiratory illness but few studies have measured the volume and type of traffic. Objective: We investigated the relation between traffic volume and respiratory health of 2328 children 9 to 11 years old in the city of Windsor, Canada. Methods: We identified the roadways within a 200 meter radius of the child's neighborhood using the latitude and longitude of the residential postal code. Traffic exposure was defined as the sum of the annual volume of vehicles on all of these roadways. Volume was calculated using sensors to detect passing vehicles (simple traffic counts), and by counts and direction of traffic at intersections (turning movement counts). Ventilatory lung function was measured by spirometry and airway inflammation by exhaled nitric oxide (eNO). Results: The odds ratio between an interquartile increase in truck turning movement counts and chest congestion was 1.20 (1.06-1.35). The percentage of predicted FVC declined 0.68%, (95% CI 1.32, 0.03) for an interquartile increase in simple traffic counts (33,787 vehicles daily). Among those with self-reported asthma, effect sizes were larger. Percentage predicted FEV 1 declined 1.84% (95% CI 0.07, 3.61) associated with an interquartile range increase in turning movement counts. No statistically significant change was detected between traffic measures and exhaled nitric oxide. Conclusions: Our findings provide further support for the hypothesis that neighborhood exposure to traffic-related air pollution increases respiratory symptoms and reduces ventilatory function in children, especially those with self-reported asthma.
BMC Public Health, 2010
Background: Most epidemiologic studies use traffic at residential address as a surrogate for total traffic exposure when investigating effects of traffic on respiratory health. This study used GIS (Geographical Information Systems) to estimate traffic exposure, not only on residential, but also on workplace address, in addition to survey questions on time spent in traffic during commuting or other daily activities. The aim was to investigate 1) if there is an association between traffic exposure and prevalence of adult asthma and asthma symptoms, and 2) if so, does this association become stronger using more complete traffic exposure information.