Effect of HEPA Air Filters on Subclinical Markers of Cardiovascular Health (WEST)

This study has been completed.
University of British Columbia
Health Canada
Ministry of Environment, British Columbia
Information provided by:
Simon Fraser University
ClinicalTrials.gov Identifier:
First received: December 8, 2010
Last updated: NA
Last verified: December 2010
History: No changes posted
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 woodsmoke air pollution indoors and to improve subclinical indicators of microvascular function, systemic inflammation, and oxidative stress among healthy adult participants.

Condition Intervention
Endothelial Function.
Oxidative Stress.
Systemic Inflammation.
Device: HEPA filter

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single Blind (Subject)
Primary Purpose: Prevention
Official Title: Assessing the Impact of Wood Stove Interventions on Air Quality

Further study details as provided by Simon Fraser University:

Primary Outcome Measures:
  • Reactive hyperemia index [ Time Frame: After 1 week of air filtration ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • C-reactive protein [ Time Frame: After 1 week of filtration ] [ Designated as safety issue: No ]

Enrollment: 56
Study Start Date: November 2008
Study Completion Date: April 2009
Primary Completion Date: April 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Indoor air HEPA filtration
HEPA filters operating in the participant's bedroom and living room.
Device: HEPA filter
Other Names:
  • Honeywell model 50300
  • Honeywell model 18150

Detailed Description:
The investigators will use portable HEPA filters in a single-blind randomized crossover design. Each participant's home will be monitored for two consecutive seven-day periods, during which time two HEPA units (one in the bedroom and one in the main living room) will be operated indoors. During one 7-day period the HEPA filters will be operated normally, and during the other period the HEPA unit will be operated without the internal filter in place (i.e., "placebo filtration"), thus blinding participants to the filters' status. The order of filtration or non-filtration will be random. At the end of each 7-day period microvascular function will be assessed, blood will be collected for assessment of systemic inflammatory markers, and urine will be collected for assessment of oxidative stress markers.

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

Inclusion Criteria:

  • 19 years or older
  • Non-smoking household
  • Lives in study region (Smithers or Telkwa British Columbia)

Exclusion Criteria:

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Please refer to this study by its ClinicalTrials.gov identifier: NCT01256957

Canada, British Columbia
Simon Fraser University
Burnaby, British Columbia, Canada, V5A 1S6
Sponsors and Collaborators
Simon Fraser University
University of British Columbia
Health Canada
Ministry of Environment, British Columbia
Principal Investigator: Ryan Allen, PhD Simon Fraser University
  More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Ryan Allen, Simon Fraser University
ClinicalTrials.gov Identifier: NCT01256957     History of Changes
Other Study ID Numbers: 869329 
Study First Received: December 8, 2010
Last Updated: December 8, 2010
Health Authority: Canada: Ethics Review Committee

Additional relevant MeSH terms:
Pathologic Processes

ClinicalTrials.gov processed this record on May 30, 2016