Clinical trial NCT01617330: Controlled Exposure to Diesel Exhaust in Subjects With Allergic Rhinitis
Official title: Controlled Exposure to Diesel Exhaust in Subjects With Allergic Rhinitis
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Allergic Rhinitis
Keywords: Particulate matter
Air pollution
Diesel exhaust
Allergic rhinitis
Lead sponsor: University Hospital, Umeå
Sponsor class: OTHER
Collaborators: name: King's College London
First posted: 2012-06-12
Enrollment: 14
Sex: ALL
Minimum age (years): 20
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: Proximity to traffic, particularly to diesel-powered heavy-duty vehicles, has been associated with inducing and enhancing allergies in children and adults. To investigate the basis for this association, a controlled exposure of allergic rhinitics to diesel exhaust was performed at a dose known to be pro-inflammatory in healthy individuals.

The hypothesis was that airway inflammation would be augmented in allergic rhinitics following exposure to diesel exhaust at an environmentally pertinent particulate matter concentration.

Fourteen allergic rhinitics were exposed in a double-blinded, randomised trial to both diesel exhaust at 100 microgram/m3 PM10 (representing an aerosol of nanoparticulate combustion particles, mean diameter 80 nm) and filtered air for two hours on separate occasions. Bronchoscopy with endobronchial mucosal biopsies and airway lavage was performed 18 hours post-exposure, and samples were analysed for markers of inflammation.


Eligibility criteria: Inclusion Criteria:

* History of seasonal allergic rhinitis requiring medical treatment only during the pollen season and were classified as mild and intermittent according to ARIA guidelines.
* Positive skin prick test to airborne allergens
* Normal lung function
* Negative Metacholine challenge

Exclusion Criteria:

* Current smoking or a previous history of smoking.
* Asthma
* Chest infection within six weeks prior to or during the study
* Current use of non-steroidal anti-inflammatory drugs
* Current vitamin C or E supplementation
* Current use of topical nasal steroids.

Primary outcomes:
measure: Airway inflammation
timeFrame: 18 hours post exposure
Secondary outcomes:
Other outcomes:
Locations:
city: Umeå
country: Sweden
facility: Department of Public Health and Clinical Medicine, Division of medicine, Pulmonary medicine
state: Sverige
Study officials:
affiliation: Department of Public Health and Clinical Medicine, Division of medicine, Umeå University, Umeå
name: Annelie F Behndig, MD PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Morgenstern V, Zutavern A, Cyrys J, Brockow I, Koletzko S, Kramer U, Behrendt H, Herbarth O, von Berg A, Bauer CP, Wichmann HE, Heinrich J; GINI Study Group; LISA Study Group. Atopic diseases, allergic sensitization, and exposure to traffic-related air pollution in children. Am J Respir Crit Care Med. 2008 Jun 15;177(12):1331-7. doi: 10.1164/rccm.200701-036OC. Epub 2008 Mar 12.
citation: Gehring U, Wijga AH, Brauer M, Fischer P, de Jongste JC, Kerkhof M, Oldenwening M, Smit HA, Brunekreef B. Traffic-related air pollution and the development of asthma and allergies during the first 8 years of life. Am J Respir Crit Care Med. 2010 Mar 15;181(6):596-603. doi: 10.1164/rccm.200906-0858OC. Epub 2009 Dec 3.
citation: Oftedal B, Brunekreef B, Nystad W, Nafstad P. Residential outdoor air pollution and allergen sensitization in schoolchildren in Oslo, Norway. Clin Exp Allergy. 2007 Nov;37(11):1632-40. doi: 10.1111/j.1365-2222.2007.02823.x. Epub 2007 Sep 17.
citation: Behndig AF, Larsson N, Brown JL, Stenfors N, Helleday R, Duggan ST, Dove RE, Wilson SJ, Sandstrom T, Kelly FJ, Mudway IS, Blomberg A. Proinflammatory doses of diesel exhaust in healthy subjects fail to elicit equivalent or augmented airway inflammation in subjects with asthma. Thorax. 2011 Jan;66(1):12-9. doi: 10.1136/thx.2010.140053. Epub 2010 Sep 13.
citation: Brown JL, Behndig AF, Sekerel BE, Pourazar J, Blomberg A, Kelly FJ, Sandstrom T, Frew AJ, Wilson SJ. Lower airways inflammation in allergic rhinitics: a comparison with asthmatics and normal controls. Clin Exp Allergy. 2007 May;37(5):688-95. doi: 10.1111/j.1365-2222.2007.02695.x.