Relationship of Ambient Particulate Matter to Heart Rate Variability and Cardiac Arrhythmias in Elderly Adults with Coronary Artery DiseaseEPA Grant Number: R826783
Title: Relationship of Ambient Particulate Matter to Heart Rate Variability and Cardiac Arrhythmias in Elderly Adults with Coronary Artery Disease
Investigators: Ostro, Bart , Bolton, Merle , Lipsett, Michael , Tager, Ira , Woo, Mary
Institution: Public Health Institute , California Office of Environmental Health Hazard Assessment , Eisenhower Medical Center , University of California - Berkeley , University of California - Los Angeles , University of California - San Francisco
EPA Project Officer: Chung, Serena
Project Period: October 1, 1998 through September 30, 2000
Project Amount: $436,964
RFA: Health Effects of Particulate Matter and Associated Air Pollutants (1998) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Health Effects , Particulate Matter , Air
Description:Information regarding variability in urban air toxics emissions is needed to identify high emitters or highly exposed populations. Information regarding uncertainty is needed to characterize the quality of an emissions inventory and to target data collection to reduce uncertainty. Our objectives are: (1) to develop methods for quantifying variability and uncertainty in urban air toxics emissions; (2) to develop methods for identifying key sources of variability and uncertainty in assessments of urban air toxic emissions and exposures; (3) to develop probabilistic process engineering models for making realistic estimates of emissions of, and the effects of control measures for, urban air toxics; (4) to demonstrate the methods via a detailed case study of urban air toxics emissions and exposures; and (5) to characterize the benefits of the methods with respect to environmental and research management.
Approach:Adults (aged 65-80) with coronary artery disease will be recruited from a large cardiology practice in the Coachella Valley, CA, an area where the PM mass is dominated by coarse particles and which has been designated to be in serious nonattainment with the 24-hour PM10 national ambient air quality standard (NAAQS). Health data will consist of subjects' responses to a structured interview, supplemented with abstraction of their medical records, pulmonary function testing and, to assess HRV and cardiac arrhythmias, serial 24-hour Holter monitoring. These monitors will be run at weekly intervals for up to 12 consecutive weeks from April - June 2000, when seasonal trends favor high ambient levels of PM. The methods to be used will be pilot-tested in spring 1999, allowing an assessment of the feasibility of 24-hour versus shorter intervals of Holter monitoring, among other things. Exposure measures will consist of real-time monitoring of ambient PM10, PM2.5, ultrafine particles, ozone, nitrogen dioxide, and carbon monoxide. The exposure assessment will be refined with PM measurements inside and outside of study subjects' homes. Analysis will use statistical methods developed for analyzing longitudinal data using linear mixed models (SAS Proc Mixed procedure) to account for within-subject correlation.
Expected Results:This study will test the hypotheses that several measures of PM (PM10, PM2.5, coarse particles and ultrafine particles) are associated with two outcomes that may help explain PM-mortality associations: decreased HRV and increased ventricular arrhythmias in a potentially vulnerable subpopulation.
Improvements in Risk Assessment or Risk Management: This project will help elucidate the relative roles (if any) of exposure to several subfractions of PM10 in an area in which the particulate mass is dominated by coarse particles. As indicated in the U.S. EPA's recent review and revision of the PM NAAQS, there are almost no studies of the relationships of coarse or ultrafine particles to morbidity or mortality: the proposed study offers the opportunity to investigate the relative importance of both.