2010 Progress Report: Development of Exposure and Health Outcome Indicators for Those with Asthma or Other Respiratory ProblemsEPA Grant Number: R833629
Title: Development of Exposure and Health Outcome Indicators for Those with Asthma or Other Respiratory Problems
Investigators: Meng, Ying-Ying , Jerrett, Michael , Ritz, Beate R. , Wilhelm, Michelle
Institution: University of California - Los Angeles
EPA Project Officer: Nolt-Helms, Cynthia
Project Period: September 1, 2007 through August 31, 2010 (Extended to February 29, 2012)
Project Period Covered by this Report: November 7, 2009 through November 6,2010
Project Amount: $500,000
RFA: Development of Environmental Health Outcome Indicators (2006) RFA Text | Recipients Lists
Research Category: Health Effects , Health
This research will investigate the feasibility of combining existing environmental monitoring and health survey data (California Health Interview Survey (CHIS)) to develop health outcome indicators, such as asthma-related emergency department (ED) visits, doctor’s visits, absences from school/work, medication use, and frequency of asthma symptoms for those with asthma, as well as asthma-like symptoms, doctor’s visits and absences from work/school due to breathing problems for those without asthma diagnoses.
We have developed several long-term (12-, 24- and 36-month) criteria air pollutant exposure indicators for all CHIS 2003 respondents and 2005 asthmatic respondents using existing measurement data for O3, NO2, PM10, and PM2.5 from California Air Resources Board (CARB) ambient air monitors. Additionally, we have explored exposure indicators using geostatistical modeling (e.g., kriging for O3, and land use regression (LUR) for PM10, PM2.5, NOx, NO and NO2) for CHIS 2005 respondents in Los Angeles. We have found that ordinary kriging for O3 and universal kriging for PM2.5 and PM10 produced reasonable predictions on cross validation, while the scarcity of monitors precluded generating land use regressions for PM10 and PM2.5. We also have developed traffic-related exposure indicators based on residential traffic density and proximity to roadways for all CHIS 2003 respondents and 2005 asthmatic respondents. In addition to descriptive analyses looking at outcome and exposure distributions, we looked at raw and adjusted odds ratios for annual pollutant averages and asthma health outcomes, more specifically asthma ED visits, daily asthma medication use, asthma attacks, daily/weekly asthma symptoms, and missed school/work days due to asthma. We also examined the distribution of exposures and outcomes by income and race to identify susceptible sub-populations. Lastly, we have updated our literature review on asthma, air pollution, and related susceptibility factors such as comorbidities, neighborhood environment, and socioeconomic status.
We will continue to investigate spatial and temporal links between the exposure indicators and health outcome indicators, such as asthma-related ED visits, doctor’s visits, absences from school/work, medication use, and frequency of asthma symptoms for those with asthma, as well as asthma-like symptoms, doctor’s visits and absences from work/school due to breathing problems for those without asthma diagnoses after adjusting for other factors. We also will identify whether the types of health outcomes (e.g., prevalence of persistent asthma or prevalence of asthma-like symptoms) and the magnitude of associations estimated for our air pollution exposure indicators differ by type of area (e.g., rural and urban) and by sub-population (e.g., children and the elderly, or racial and ethnic groups).