Investigating obesity as a susceptibility factor for air pollution in childhood

EPA Grant Number: R836152C001
Subproject: this is subproject number 001 , established and managed by the Center Director under grant R836152
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Center for the Study of Childhood Asthma in the Urban Environment
Center Director: Hansel, Nadia
Title: Investigating obesity as a susceptibility factor for air pollution in childhood
Investigators: McCormack, Meredith , Hansel, Nadia , Paulin, Laura , Schneider, Hartmut , Sterni, Laura M
Current Investigators: McCormack, Meredith , Hansel, Nadia
Institution: The Johns Hopkins University
EPA Project Officer: Louie, Nica
Project Period: September 1, 2015 through August 31, 2019
RFA: Children's Environmental Health and Disease Prevention Research Centers (2014) RFA Text |  Recipients Lists
Research Category: Health , Children's Health

Objective:

Provide experimental evidence of the effect of being overweight on air pollution susceptibility and identification of plausible mediators of this effect.

Approach:

To provide experimental evidence, Project 1 will conduct a randomized, clinical trial of an air purifier intervention to address our overarching hypothesize that overweight children are more susceptible to PM compared to lean children. Portable air purifiers have been used successfully in clinical trials of inner-city children, reduce indoor PM by ≥50%, and reduce asthma symptoms. Moreover, air purifiers are a highly feasible, inexpensive intervention that can be implemented immediately to modify indoor environments. To define plausible mediators of effect, we will investigate four leading hypotheses that increases in 1) tidal volume and thereby increases in particulate dose to the lungs 2) systemic inflammation and oxidative stress that may result in exaggerated responses to pro-inflammatory PM exposure 3) glucocorticoid resistance which may dampen the protective effect of inhaled steroids 4) risk of obstructive sleep apnea (OSA), a comorbidity recently linked to PM exposure that is also associated with worsening of asthma symptoms, enhance susceptibility to PM among overweight versus lean children. The study findings will be critical to future revisions of air quality standards and have high potential to impact policy by defining a new sensitive population to pollution health effects. Further, our findings will immediately impact asthma clinical practice guidelines by providing evidence to support a highly feasible intervention for the highest risk subpopulation of children with asthma, a population easily identifiable by height and weight measurements. Moreover, as our target population is low-income, minority children, our findings will have implications for those most affected by both obesity and asthma.

Rationale:

Asthma and obesity are public health crises that have concurrently arisen over the past decades, affecting millions of children in the US and disproportionately affecting low-income minority children in urban areas. The same children at highest risk for asthma and obesity also have greater exposure to pollution. Emerging evidence suggests that these three factors –asthma, obesity, and pollution– may be causally linked. Recent observational studies have found that obesity confers susceptibility to pulmonary effects of particulate matter (PM), including our own showing overweight Baltimore children with asthma have greater respiratory response to indoor PM versus lean children. There is a need to confirm these observational findings with causal-level evidence, including experimental evidence of the effect of being overweight on PM susceptibility and identification of plausible mediators of this effect.

Progress and Final Reports:

2016 Progress Report
2017 Progress Report


Main Center Abstract and Reports:

R836152    Center for the Study of Childhood Asthma in the Urban Environment

Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R836152C001 Investigating obesity as a susceptibility factor for air pollution in childhood
R836152C002 Novel exposure metrics for assessing the effects of ultrafine and fine particulate matter on asthma in children
R836152C003 The Role of Obesity in Biological Responses to Particulate Matter in Mice