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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01256957
Recruitment Status : Completed
First Posted : December 9, 2010
Last Update Posted : December 5, 2016
University of British Columbia
Health Canada
Ministry of Environment, British Columbia
Information provided by (Responsible Party):
Ryan Allen, Simon Fraser University

Brief Summary:
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 or disease Intervention/treatment Phase
Endothelial Function Oxidative Stress Systemic Inflammation Device: HEPA filter Not Applicable

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.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 56 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single (Participant)
Primary Purpose: Prevention
Official Title: Assessing the Impact of Wood Stove Interventions on Air Quality
Study Start Date : November 2008
Actual Primary Completion Date : April 2009
Actual Study Completion Date : April 2009

Arm Intervention/treatment
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

No Intervention: Control

Primary Outcome Measures :
  1. Reactive hyperemia index [ Time Frame: After 1 week of air filtration ]

Secondary Outcome Measures :
  1. C-reactive protein [ Time Frame: After 1 week of filtration ]

Information from the National Library of Medicine

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, Learn About Clinical Studies.

Ages Eligible for Study:   19 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

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

Exclusion Criteria:

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): 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

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Ryan Allen, Associate Professor, Simon Fraser University Identifier: NCT01256957     History of Changes
Other Study ID Numbers: 869329
First Posted: December 9, 2010    Key Record Dates
Last Update Posted: December 5, 2016
Last Verified: December 2010

Additional relevant MeSH terms:
Pathologic Processes