Hypertension in Mexican-Americans: Assessing Disparities in Air Pollutant RisksEPA Grant Number: R834581
Title: Hypertension in Mexican-Americans: Assessing Disparities in Air Pollutant Risks
Investigators: Symanski, Elaine , Bondy, Melissa L. , Chan, Wenyaw , Chen, Lin-An , Fernandez-Esquer, Maria E. , Piller, Linda B.
Current Investigators: Symanski, Elaine , Bondy, Melissa L. , Chan, Wenyaw , Chen, Lin-An , Jimenez, Maria , Strom, Sara
Institution: The University of Texas School of Public Health , National Chiao-Tung University , The University of Texas MD Anderson Cancer Center
EPA Project Officer: Breville, Maggie
Project Period: August 1, 2010 through July 31, 2014 (Extended to July 31, 2016)
Project Amount: $1,250,000
RFA: Understanding the Role of Nonchemical Stressors and Developing Analytic Methods for Cumulative Risk Assessments (2009) RFA Text | Recipients Lists
Research Category: Health Effects , Human Health Risk Assessment , Health
The incidence of hypertension, a key risk factor for cardiovascular diseases (CVD), has been growing in the United States (U.S.) and CVD remains the leading cause of death among the U.S. Hispanic population. We will examine the association between fine particulates and other air pollutants and hypertension, with a focus on quantifying modifying effects of nonchemical stressors on air pollutant effects. Novel methods for addressing interactions between chemical and non-chemical stressors in a logistic regression context will be developed. We will also develop a community-based research participatory approach that involves both advisory and focus groups.
Several studies have shown an association between air pollutants and hypertension via oxidative stress and inflammatory pathways. Yet, little is known about the modifying effects of nonchemical stressors on air pollutant risks for hypertension. We will assess the hypothesis that individual- and neighborhood-level psychosocial stressors exacerbate risks for hypertension associated with air pollution among Mexican-Americans. The objectives of the study are to: (1) Develop new statistical methods that allow for a rigorous evaluation in a logistic regression framework of interaction between chemical and non-chemical stressors; (2) Estimate exposure to psychosocial stressors and air pollutants; and (3) Apply traditional and newly developed methods to examine effects of fine particulates and other air pollutants on the prevalence of hypertension, with control for important confounders. Modifying effects of nonchemical stressors on air pollutant effects will be examined.
We will use a unique dataset from an ongoing cohort study of Mexican-Americans in Houston, Texas. Houston’s poor air quality and its location in a state ranked among the nation’s worst in health, social and economic disparities makes it is an ideal region to study the interacting effects of air pollution and psychosocial stressors on adverse health outcomes. Focus groups will be used to inform the collection of additional and culturally-relevant data that are related to the most critical mediating factors that affect air pollutant risks for hypertension. A community advisory group will be established to provide guidance, validation and feedback to all project activities. We will develop new statistical methods to evaluate interactions between chemical and non-chemical stressors; estimate exposure to psychosocial stressors and air pollutants; and examine modifying effects of psychosocial stressors on associations between air pollution and hypertension using a traditional approach, as well as the methods developed in the study for examining interactions between chemical and nonchemical stressors.
We will generate novel methods for evaluating interactions between key risk factors. This will allow us to elucidate which psychosocial stressors operate as principal mediators of air pollutant health risks and identify vulnerable subgroups in the Mexican-American community. We will also enhance community capacity to identify air pollutant and psychosocial stressors that increase risks of hypertension among Mexican-Americans in Houston. Results will inform risk assessors about combined effects arising from multiple stressors and aid in the development of multi-factorial interventions to reduce disparities in cardiovascular health among vulnerable populations in large urban areas.