Exposure to Fine Particulate Matter and Acute Effects on Blood Pressure: Effect Modification by Measures of Obesity and Location
- Srimathi Kannan1,*,
- Timothy Dvonch2,
- Amy J Schulz3,
- Barbara A Israel3,
- Graciela Mentz3,
- James House4,
- Paul Max5,
- Angela G Reyes6
- 1 School of Public Health and Health Sciences, University of Massachusetts, United States;
- 2 Department of Environmental Health Sciences, University of Michigan School of Public Health, United States;
- 3 Department of Health Behavior and Health Education, University of Michigan School of Public Health, United States;
- 4 Survey Research Center and Sociology Department, University of Michigan, United States;
- 5 Detroit Department of Health and Wellness Promotion, United States;
- 6 Detroit Hispanic Development Corporation, United States
- Correspondence to: Srimathi Kannan, Nutrition, University of Massachusetts, Department of Nutrition, 224 Chenoweth Laboratory, 100 Holdsworth Way, School of Public Health and Health Sciences, Amherst, 01003, United States; srimathik{at}gmail.com
- Received 16 September 2008
- Accepted 29 June 2009
- Published Online First 15 October 2009
Abstract
Background: Observational studies and controlled experiments have provided evidence that airborne particulate matter (PM) is capable of acutely increasing blood pressure (BP) in certain scenarios. The goal of this study is to evaluate whether and to what extent obesity and community location affect relationships between fine particulate matter (PM2.5) and blood pressure (BP) measures.
Methods: Using data from a stratified random sample survey of adults conducted in 2002-2003 in Detroit, Michigan, we tested body mass index (BMI) and waist circumference (WCIR) in separate models as effect modifiers of the relationship between PM2.5 exposure and BP. We also tested interactions with community location. Models were adjusted for covariates with established pro-hypertensive effects.
Results: PM2.5 exposure was positively associated with increased pulse pressure (PP) for those categorized as obese (BMI ≥30) across lags 2 (β4.16, p<0.05) and 3 days (β2.55, p<0.05) prior to BP measure. WCIR similarly modified the effect of exposure to PM2.5 on PP (β4.34, p<0.003). The observed effects were enhanced in the community with closer proximity to local emissions of PM2.5, and for residents classified as obese (BMI>30) or with WC above high risk cuts points.
Conclusions: This community-based study suggests that positive associations between PM2.5 exposure and PP and SBP are enhanced in areas proximate to sources of PM 2.5 emissions. These patterns were observed for all residents, but were more visible and consistent among those who were obese. Research is needed to examine the mechanistic pathways by which air particles interact with obesity and location to affect BP, and inform community interventions to reduce the population burden of hypertension and related co-morbidities.
