childhood asthma and air quality in louisville,...
TRANSCRIPT
10/30/2012
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Childhood Asthma and Air Quality in Louisville, Kentucky
Carol Hanchette
Department of Geography & Geosciences
University of Louisville
(with Jong-Hyung Lee and Tim E. Aldrich)
Study Goal
• Use GIS and statistical analysis to examine air quality and asthma occurrence among urban children in Louisville.
Asthma
• Asthma one of the most common serious chronic diseases of childhood
• Inflamed and constricted airways breathing difficulties
• Coughing, shortness of breath, wheezing, tightness in the chest
Asthma
• Third leading diagnosis for hospitalization among children
• In 2010, one in 11 U.S. children had asthma (7 million, 9%)
• 12% increase from 2001-2009 (all ages)
• Kentucky rates (2009 Asthma Surveillance Report)
• 10.6% < 11 years, 13.6% middle school, 11.8% high school
• Rates for African American high school students double those for whites
• Prevalence highest in Appalachia
• Louisville one of 100 worst cities in U.S. for people with asthma (ranking = 53)
Akinbami, L.J., Moorman, J.E., Garbe, P.L., & Sondik, E.J. 2009. Status of childhood asthma in the United States, 1980-2007. Pediatrics 123,S131-S145.
American Lung Association. 2008. Lung Disease Data. Retrieved on February 9, 2010 at http://www.lungusa.org/about-us/publications/
Centers for Disease Control and Prevention. 2011. Vital signs: Asthma prevalence, disease characteristics, and self-management education --- United States, 2001—2009. MMWR 60(17);547-552.
Asthma Triggers
• Dust mites
• Molds
• Cockroaches
• Pet dander
• Secondhand smoke
• Ozone and particulate matter
• Leaf mold (alternaria, cladosporium)
Asthma in Louisville: Recent Studies • Strong spatial patterns and seasonal variations
• Jones et al. (2004): highest rates in NW Louisville
• Louisville Metro Housing Coalition (2005): same pattern
• Lee (2006): strong seasonal pattern – summer trough and fall peak (2003-04 data)
• Differs from statewide seasonal pattern of winter peak, followed by fall
• Lee (2006): precipitation (R=0.28), PM2.5 (R=0.32)
• Northwestern Louisville: high African-American population, high poverty rates environmental justice concerns
Jones, V. F., Lawson, P., Robson, G., Buchanan, B. and Aldrich, T. (2004). The use of spatial statistics to identify asthma risk factors in an urban community. Pediatric Asthma, Allergy & Immunology, 17,3-13.
Lee, Jong-Hyung. (2006). Pediatric Asthma Admissions and Seasonal Variables in Jefferson County, Kentucky. Senior undergraduate thesis, Department of Geography and Geosciences, University of Louisville, Louisville, KY.
Louisville Metro Housing Coalition, March 2005. Out of Breath: Childhood Asthma, Poverty and Housing. Available at: http://www.metropolitanhousing.org/index.cfm?article_id=63
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Current Study
• Hospital discharge data
• 2005-2008
• Children 0-19
• Jefferson County
Characteristic Number of Cases Percent of Cases*
Gender
Male 1078 58.1
Female 778 41.9
Age in Years
0-4 930 50.1
5-9 495 26.7
10-14 261 14.1
15-19 170 9.2
Referral source
Physician 389 21.0
Emergency
department
1456 78.4
Other 11 0.6
Insurance Type
Commercial 452 24.4
Federal program 1245 67.1
Other 159 8.6
Total 1856 100
Year # Discharges Population Rate per 100,000
2005 424 184,564 229.73
2006 421 185,620 226.81
2007 484 186,963 258.87
2008 527 189,122 278.66
All Years 1856 746,269 248.70
Spatial Patterns
• Choropleth mapping (USPS Zip Codes)
• Local Index of Spatial Autocorrelation (LISA)*
*Empirical Bayes LISA option, queen’s contiguity, spatial lag of 1, Moran’s I = 0.5961
Environmental Justice Issues Disproportionate Siting vs. Minority Move-In
Shading = Census tracts greater than 50% African-American
Socio-Economic Issues
Study Area*
* Six zip codes: 40203, 40210, 40211, 40212, 40215, and 40216
Data and Methods
• Seasonal Trends
• Asthma hospitalizations for the 6 study zip codes (n=832)
• Coded by season (solstice and equinox dates)
• ANOVA with square-root transformation of counts
• Tukey’s least significant difference test
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Data and Methods
• Air Pollutants
• EPA criteria pollutants (CO, NO2, O3, PM2.5, SO2)
• Continuous monitoring, 1-h averages
• PM2.5 24-h average
• O3 March 1 – October 31
• Six chemical compounds Louisville Firearms Training Site (West Jefferson Community Task Force)
• 1,3 butadiene, acetone, acrylonitrile, benzene, chloroform, toluene (12-day sampling frequency)
• Bivariate correlations: average and maximum, Spearman’s rank
• Exposure lag of 0 (same-day)
Air Pollutant Monitoring Sites
Seasonal Trends
Year/Season Number Percent
Winter 146 17.5
Spring 169 20.3
Summer 187 22.5
Fall 330 39.7
Total 832 100.0
p = 0.01 Greatest difference: fall vs. other seasons No post-2005 summer trough
Air Pollutants
Air Pollutants
Pollutant/VOC Sampling Frequency No. Records Days with cases R
1,3-Butadiene varied 54 24 -.134
Acetone 12 days 108 48 .034
Acrylonitrile varied 34 19 .199
Benzene 12 days 106 48 -.099
Chloroform varied 41 20 -.130
Toluene 12 days 107 47 .030
• All correlations with criteria pollutants negative
• Correlations with compounds negative or low
• Acrylonitrile R = 0.199
• Lack of data aggregation (daily counts)
Seasons vs. School Year
Year In School Rate Out of School Rate
2005 0.8851 0.4712
2006 0.75 0.5078
2007 0.8994 0.5484
2008 0.9881 0.6263
All Years 0.8802 0.5391
• Summer trough disappeared after 2005
• Asthma rates jump in mid-August
• Academic calendars for 2005-2008
• Binary coding (0 = not in school, 1 = in school)
• Accounted for summers, weekends, school holidays, teacher work days
• For all years, in-school rates higher than out-of-school rates
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Discussion and Conclusions
• Well-defined spatial and temporal patterns of childhood asthma in Louisville
• Negative correlations with criteria pollutants? Location of monitoring sites, monitoring frequency, time lag of 0
• Further investigation into higher in-school rates
Tables and Graphics from
• Hanchette, C.L., Aldrich, T.E. and Lee, J-H. 2011. Asthma, Air Quality and Environmental Justice in Louisville, Kentucky. In, Maantay, J.A., and McLafferty, S. (eds.), Geospatial Analysis for Environmental Health, pp. 223-242. New York: Springer-Verlag.