Wood Stove Interventions and Child Respiratory Health

Summary

Acute lower respiratory tract infections (LRTIs) account for more than 27% of all hospitalizations among US children under five years of age, with recurrent LRTIs in children a recognized risk factor for asthma. Residential biomass combustion leads to elevated indoor levels of fine particulate matter (PM2.5) that often exceed current health-based air quality standards. PM2.5 exposure is associated with many adverse health outcomes, including a greater than three-fold increased risk of LRTIs. To date, exposure reduction strategies in wood stove homes have been either inconsistently effective or include factors that limit widespread dissemination and continued compliance in rural and economically disadvantaged populations. In this project, the investigators propose to test the efficacy of two intervention strategies for reducing indoor wood smoke PM2.5 exposures and children's risk of LRTI in three unique and underserved settings: (1) rural mountain valley communities in western Montana; (2) Navajo Nation communities; and (3) Alaska Native Villages. The investigators will conduct a three-arm randomized placebo-controlled post-only intervention trial in wood stove homes with children less than five years old. Education on best-burn practices and training on the use of simple instruments (i.e., stove thermometers and wood moisture meters) will be introduced as one intervention arm (Tx1). This intervention will be evaluated against an indoor air filtration unit arm (Tx2), as well as a placebo arm (Tx3, sham air filters). The primary outcome will be LRTI incidence among children under five years of age. To allow for detection of exposure and outcome differences within each of the three regions, a sample of 324 homes, or 108 within each study area will be equally assigned to each of the three intervention arms. The overall hypothesis is that a low-cost, educational intervention targeting indoor wood smoke PM2.5 exposures will be sustainable, and can reduce children's risk of LRTI in underserved Native and rural communities.

Conditions

• Lower Tract Respiratory Infection

Interventions

BEHAVIORAL

Education Intervention (Tx1)

The intervention will be a combination of a strong education campaign coupled with the distribution of inexpensive tools to the homes that will enable the residents to burn wood more efficiently.

DEVICE

Air Filtration Unit Treatment (Tx2)

A 20" x 18" Filtrete air filtration unit (Ultra Clean Air Purifiers, 3M, St. Paul, MN) will be placed in the same room as the wood stove. These units are rated by their ability to provide an equivalent amount of contaminant free air into the space, and have a smoke Clean Air Delivery Rate of 112. The electrostatically charged filters in these units are approximately 85% efficient at removing 0.2 micron particles (cigarette smoke size particles) and over 95% efficient at removing 3 micron particles. The unit will be operated on the "high" setting throughout the duration of the six-month assessment winter periods. Filters will be changed out by the Community Coordinator approximately once per month in an effort to maximize collection efficiency.

DEVICE

Placebo Intervention (Tx3)

Similar to Tx1, a 20" x 18" Filtrete air filtration unit will be installed within the wood stove home. Instead of a high efficiency filter, the units will utilize a placebo filter.

Sponsors & Collaborators

• National Institute of Environmental Health Sciences (NIEHS)

  collaborator NIH

• University of Montana

  lead OTHER

Principal Investigators

• Curtis W Noonan, Ph.D. · University of Montana

• Tony J Ward, Ph.D. · University of Montana

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Model

PARALLEL

Eligibility

Max Age

5 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2014-11-30

Primary Completion

2020-03-31

Completion

2020-03-31

Countries

• United States

Study Locations