Face Masks to Reduce the Adverse Effects of Diesel Exhaust Inhalation

Not Applicable

Completed

• Conditions: Healthy
• Interventions: Other: Diesel exhaust exposure with sham mask; Other: Diesel exhaust exposure with filtered facemask

• Registration Number: NCT02729129
• Lead Sponsor: Umeå University

Brief Summary

Air pollution exposure is a major environmental and public health concern. The findings from controlled exposure studies have given biological plausibility to the epidemiological associations, and have defined important pathways that may be amenable to intervention. Ultimately, there is a need to address how one may protect the public from these detrimental effects. Two studies have been performed assessing the cardiovascular effects of wearing a face mask in a highly polluted urban area in China in healthy volunteers and patients with coronary heart disease. These demonstrated lower blood pressure and increased heart rate variability when wearing a face mask as compared to not. The investigators aim to test if wearing a highly efficient face mask during exposure to dilute diesel exhaust abrogates the well-known adverse cardiovascular effects.

Detailed Description

Not available

Study Timeline

• Study Start: 2014-04
• Primary Completion: 2015-02
• Study Completion: 2016-02
• Study First Submitted: 2016-03-18
• Status Verified: 2016-04
• Study First Submitted QC: 2016-04-05
• Study First Posted: 2016-04-06
• Last Update Submitted: 2016-04-06
• Last Update Posted: 2016-04-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 22

Inclusion Criteria

• Healthy males
• Non-smoking
• All subjects undergo a general health examination and are required to have normal clinical examination, ECG, blood tests and lung function

Exclusion Criteria

• Metabolic or cardiovascular disease
• Asthma or other respiratory disease
• Respiratory infection within 2 weeks of the study
• Antioxidant- and/or vitamin supplementation within 1 week prior to, as well as during the course of the study. (incl vitamin C, Acetylcysteine)
• Smokers or regular snus usage

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Sham facemask	Diesel exhaust exposure with sham mask	-
Commercially available highly-efficient facemask	Diesel exhaust exposure with filtered facemask	-

Primary Outcome Measures

Name	Time	Method
Vascular vasomotor function	2 hours	Forearm venous occlusion plethysmography to measure forearm blood flow during unilateral intrabrachial infusion of endothelial-dependent and -independent vasodilators. Assessment is shown in ml/100ml tissue/min.

Secondary Outcome Measures

Name	Time	Method
Fibrinolytic function	2 hours	Tissue plasminogen activator was analysed in blood samples taken after bradykinin infusions in order to assess fibrinolytic function (ng/ml).
Blood pressure	24 hours	Ambulatory blood pressure monitors are worn by subjects for 24 hours during and after exposure.
Heart rate variability	24 hours	Holter ECGs are worn by subjects during and for 24 hours post exposure. This will be assessed for heart rate variability (HRV).

Trial Locations

Locations (1)

Umeå University; 🇸🇪 Umeå, Sweden