Clinical trial NCT00745446: The Effect of a Retrofit Particle Trap on the Vascular Effects of Diesel Exhaust Inhalation
Official title: The Effect of a Retrofit Particle Trap on the Vascular Effects of Diesel Exhaust Inhalation
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Heart Disease
Keywords: Air pollution
Diesel exhaust
Endothelial function
Vascular function
Particle trap
Thrombosis
effects
inhalation
Lead sponsor: University of Edinburgh
Sponsor class: OTHER
Collaborators: name: Umeå University
First posted: 2008-09-03
Enrollment: 18
Sex: MALE
Minimum age (years): 18
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: The purpose of this study is to determine whether a retrofit particle trap can reduce the adverse vascular responses to diesel exhaust inhalation

Detailed description: 18 subjects healthy male volunteers will be recruited at Umeå University. In a randomised, double blind 3 way crossover trial, subjects will be exposed to filtered air, diesel exhaust (300mcg/m3) or filtered diesel exhaust for 1 hour during intermittent exercise.

2 hours following the exposure, thrombogenicity will be assessed using the Badimon chamber - an ex-vivo model of thrombosis formed under constant flow conditions.

Forearm blood flow in response to infused intra-brachial vasodilators will be measured using venous occlusion plethysmography 6 hours after the exposure.

Arterial stiffness will be measured using peripheral arterial applanation tonometry in the hour post-exposure.

Blood samples will be collected at timepoints over the 24 hours after exposure.

Eligibility criteria: Inclusion Criteria:

* Healthy male volunteers

Exclusion Criteria:

* Intercurrent illness
* Smoking
* Significant occupational exposure to air pollution
* Regular medication usage

Primary outcomes:
measure: Forearm blood flow in response to infused intra-arterial vasodilators
timeFrame: 6 hours post-exposure
Secondary outcomes:
measure: Arterial stiffness measured by applanation tonometry
timeFrame: In the 1 hour following exposure
measure: Thrombogenicity measured using the Badimon chamber - an ex-vivo model of thrombosis under conditions of continuous flow
timeFrame: 2 hours after the exposure
measure: Exhaled nitric oxide - a marker of pulmonary inflammation
timeFrame: 1 hour & 6 hours after exposure
measure: Endogenous fibrinolytic capacity - measured as net release of t-PA in response to infused bradykinin
timeFrame: 6 hours after exposure
measure: Biochemical markers of systemic inflammation
timeFrame: Baseline, 2, 6 & 24 hours
Other outcomes:
Locations:
city: Umeå
country: Sweden
facility: Umeå University
state: Västerbottens
Study officials:
affiliation: Umeå University
name: Anders Blomberg, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Lucking AJ, Lundback M, Barath SL, Mills NL, Sidhu MK, Langrish JP, Boon NA, Pourazar J, Badimon JJ, Gerlofs-Nijland ME, Cassee FR, Boman C, Donaldson K, Sandstrom T, Newby DE, Blomberg A. Particle traps prevent adverse vascular and prothrombotic effects of diesel engine exhaust inhalation in men. Circulation. 2011 Apr 26;123(16):1721-8. doi: 10.1161/CIRCULATIONAHA.110.987263. Epub 2011 Apr 11.