Cardiovascular Effects of Aerosols in Residences Study (CLEAR)

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Ryan Allen, Simon Fraser University
ClinicalTrials.gov Identifier:
NCT01570062
First received: March 15, 2012
Last updated: April 10, 2014
Last verified: April 2014
  Purpose

This study is focused on the effects of HEPA filtration to reduce exposures to combustion-derived air pollution (CDAP). Specifically, the study will evaluate the health benefits of HEPA filters and compare the cardiovascular toxicity of two major sources of CDAP, specifically traffic and residential wood combustion.

Specifically, the purpose of this study is to evaluate the ability of portable high efficiency particle air (HEPA) filters to reduce exposures to PM2.5 and air pollution indoors and to improve subclinical indicators of microvascular function and systemic inflammation among healthy adult participants.

The investigators hypothesize that HEPA filter use will help decrease indoor concentrations of CDAP thereby helping to mitigate the associated cardiovascular risks.


Condition Intervention Phase
Endothelial Dysfunction
Systemic Inflammation
Device: HEPA Filter
Device: HEPA Filtration Placebo
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Single Blind (Subject)
Primary Purpose: Prevention
Official Title: Subclinical Cardiovascular Health Benefits of Interventions to Reduce Exposure to Combustion-Derived Particulate Air Pollution

Resource links provided by NLM:


Further study details as provided by Simon Fraser University:

Primary Outcome Measures:
  • Difference in reactive hyperemia measurement after HEPA filtration [ Time Frame: after 1 week of filtration ] [ Designated as safety issue: No ]
    Participants endothelial function are tested after 1 week of HEPA filtration and after 1 week of non-HEPA filtration (placebo filtration).


Secondary Outcome Measures:
  • Difference in C-Reactive Protein after HEPA Filtration [ Time Frame: after 1 week of filtration ] [ Designated as safety issue: No ]
    Participants CRP is measured after 1 week of HEPA filtration and after 1 week of non-HEPA filtration (placebo filtration).


Enrollment: 83
Study Start Date: November 2011
Study Completion Date: August 2012
Primary Completion Date: August 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Indoor Air HEPA Filtration
HEPA filters will be placed in participant's main living area and bedroom. Actual filtration will occur during only one of the two 7-day sampling periods.
Device: HEPA Filter
Two HEPA filters will be placed in participant's homes (one in the bedroom and one in the main living area); each HEPA will run for 2 consecutive 7-day sampling sessions. During one of the 7-day sampling sessions, the HEPA filter will run without the internal filter in place (i.e., "placebo" filtration).
Other Names:
  • Living area HEPA: Honeywell, Model 50250
  • Bedroom HEPA: Honeywell, Model 18155
Placebo Comparator: HEPA Filtration Placebo
For one of two 7-day sampling sessions, HEPA filters placed in participants' homes will be run without an actual filter in the housing unit.
Device: HEPA Filtration Placebo
for one of the two 7-day sampling sessions, both HEPA filters placed in participants' homes will be run without the actual filter in the housing unit.
Other Names:
  • Living area HEPA: Honeywell, Model 50250
  • Bedroom HEPA: Honeywell, Model 18155

Detailed Description:

To address knowledge gaps about health risks of specific pollution sources and to provide new evidence on the health benefits of air pollution interventions, the objectives of this study are: 1) quantify the relationship between low-level exposures to combustion-derived PM air pollution and subclinical indicators of cardiovascular disease risk; and 2) compare the relative impact of HEPA filtration for two major PM sources (traffic and residential wood combustion) on these indicators.

The use of HEPA filters may help to mitigate cardiovascular risks factors caused by combustion-derived air pollution (CDAP), (specifically woodstove and traffic emissions). We hypothesize that HEPA filter use and improved woodstove technology will help decrease indoor occurrences of CDAP. This project will help address knowledge gaps in CDAP-related health risks and benefits of interventions. Specific objectives include establishing a relationship between exposure to CDAP and biomarkers of cardiovascular risk and evaluating the impact of HEPA filter use towards improved indoor air quality and health indicators.

  Eligibility

Ages Eligible for Study:   19 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • 19 years or older
  • non-smoking household
  • lives within study boundaries and in areas of interest

Exclusion Criteria:

  • COPD
  • asthma
  • diabetes
  • heart disease
  • hypertension
  • arthritis
  • gum disease
  • occupationally exposed to traffic exposures &/or woodsmoke
  • if female, pregnant
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01570062

Locations
Canada, British Columbia
Simon Fraser University
Burnaby, British Columbia, Canada, V5A 1S6
Sponsors and Collaborators
Simon Fraser University
Investigators
Principal Investigator: Ryan Allen, PhD Simon Fraser University, Canada
  More Information

Additional Information:
Publications:
Responsible Party: Ryan Allen, Assistant Professor, Simon Fraser University
ClinicalTrials.gov Identifier: NCT01570062     History of Changes
Other Study ID Numbers: Allen,R-MOP111042
Study First Received: March 15, 2012
Last Updated: April 10, 2014
Health Authority: Canada: Canadian Institutes of Health Research

Keywords provided by Simon Fraser University:
Inflammation
Pathologic Processes

Additional relevant MeSH terms:
Inflammation
Pathologic Processes

ClinicalTrials.gov processed this record on September 30, 2014