Effect of Woodsmoke on Vascular Function (FIREWOOD)

This study is currently recruiting participants.
Verified January 2013 by University of Edinburgh
Sponsor:
Collaborators:
Umeå University
NHS Lothian
Information provided by (Responsible Party):
University of Edinburgh
ClinicalTrials.gov Identifier:
NCT01495325
First received: October 11, 2011
Last updated: January 23, 2013
Last verified: January 2013

October 11, 2011
January 23, 2013
September 2011
January 2013   (final data collection date for primary outcome measure)
Forearm blood flow measured by venous occlusion plethysmography in response to infused vasodilators [ Time Frame: 4-6 hours after exposure ] [ Designated as safety issue: No ]
Same as current
Complete list of historical versions of study NCT01495325 on ClinicalTrials.gov Archive Site
  • Ex-vivo thrombus formation using the Badimon chamber [ Time Frame: 2 hours after exposure ] [ Designated as safety issue: No ]
  • Plasma t-PA and PAI concentrations following infusion of bradykinin [ Time Frame: During forearm study, 4-6hours after exposure ] [ Designated as safety issue: No ]
Same as current
Not Provided
Not Provided
 
Effect of Woodsmoke on Vascular Function
Effect of Woodsmoke on Vascular Function in Healthy Firefighters

Exposure to air pollution is a well established risk factor for the development of heart disease. Firefighters are exposed to excess air pollution in the form of wood smoke during the extinguishing of forest or woodland fires. Heart attacks in on-duty firefighters have been linked to specific duties and in particular fire suppression, but the reasons for this increase in risk are not well understood. Exposure to wood smoke may alter blood vessel function and increase blood clot formation to explain the link between fire suppression and heart attacks.

The investigators wish to determine the effect of exposure to wood smoke at concentrations found at the perimeter of a woodland fire on blood vessel function and clotting in healthy non-smoking male professional firefighters or volunteers. Volunteers will be studied before and after inhalation of wood smoke or clean air for one hour in a purpose built whole-body exposure chamber. The investigators will perform comprehensive vascular assessments thereafter.

Understanding the effects of wood smoke on the blood vessels and clotting will be an important first step in helping to protect firefighters from heart disease. Through research, the investigators hope to identify methods to minimise the risk of heart attacks in firefighters and understand the health effects of a major source of air pollution that is relevant to the general population.

Not Provided
Interventional
Not Provided
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Vascular Function
  • Procedure: Forearm Vascular Study
    Forearm venous occlusion plethysmography to measure forearm blood flow during intra-arterial infusion of the vasodilators Verapamil (10-100 µg/min), bradykinin (100-1000 pmol/min), sodium nitroprusside (2-8 µg/min) and Acetylcholine (5-20 µg/min).
    Other Names:
    • Other Names:
    • BK
    • SNP
    • ACh
  • Procedure: Badimon Chamber
    Ex-vivo assessment of thrombus formation using the Badimon Chamber
  • Sham Comparator: Filtered Air Exposure
    1 hour exposure to filtered air during intermittent exercise
    Interventions:
    • Procedure: Forearm Vascular Study
    • Procedure: Badimon Chamber
  • Active Comparator: Woodsmoke Exposure
    1 hour exposure to dilute woodsmoke at a concentration of 1000µg/m3 during intermittent exercise
    Interventions:
    • Procedure: Forearm Vascular Study
    • Procedure: Badimon Chamber
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruiting
20
January 2013
January 2013   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • Non-smoking healthy male firefighters or volunteers

Exclusion Criteria:

  • Current smoker or regular users of snus
  • History of lung or ischaemic heart disease
  • Malignant arrhythmia
  • Systolic blood pressure >190mmHg or <100mmHg
  • Renal or hepatic dysfunction
  • Previous history of blood dyscrasia
  • Unable to tolerate the supine position
  • Blood donation within the last 3 months
  • Recent respiratory tract infection within the past 4 weeks
  • Routine medication including aspirin and NSAIDs
Male
18 Years to 35 Years
Yes
Contact: Amanda L Hunter, MBChB +441312426437 amanda.hunter@ed.ac.uk
Contact: Jenny Bosson, MD PhD jenny.bosson@gmail.com
Sweden
 
NCT01495325
2011-194-31M, PG/11/27/28842
Yes
University of Edinburgh
University of Edinburgh
  • Umeå University
  • NHS Lothian
Study Director: Nicholas L Mills, MBChB PhD University of Edinburgh
Study Chair: David E Newby, MD PhD University of Edinburgh
Study Director: Anders Blomberg, MD PhD Umeå University
Study Director: Thomas Sandström, MD PhD Umeå Univerisity
Principal Investigator: Amanda L Hunter, MBChB University of Edinburgh
University of Edinburgh
January 2013

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP