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Principal Investigator:
Dr Murali Shyamsundar
Name of the Study
SELECT: The Study of ELEctronic Cigarette Toxicity in a human model in vivo model of inflammation and vascular dysfunction. 
Why is this Study important?
Electronic cigarettes (EC) are battery-powered devices that vaporise a variety of solutions to simulate cigarette smoking.  EC use has increased substantially, especially with adolescents. Despite their increasing popularity, the harmful effects of ECs in the lung and other systems are poorly studied.  
Early studies suggest that ECs are not harmless but there are no in depth studies on lung injury.  ECs produce fine particles, which could deposit in the lungs and lead to harm, indeed animal studies of ECs have been associated with several lung toxicities.  Furthermore, the vapour reduces indoor air quality by increasing the concentrations of particulate matter and increases concentrations of substances known to cause cancer.  There is also evidence that similar damage also occurs in blood vessels due to EC use.
What is the Research question/aim?
The aim of this project is to investigate if EC users have increased inflammation in the lungs when compared to non-users in response to a mild inhaled irritant and if it affects blood vessel function.   The participants will have special blood, urine and stool samples taken as well as a camera test of their lungs and a scan of blood vessels in their arms at baseline and then following inhalation of the irritant a few weeks later.
What the Study involves:
Visit 1- 4 hours – blood samples, PFTs and FMD  measurement 
Visit 2- 4 hours- Blood, PFTs, urine and stool sample, PFTs and bronchoscopy
Visit 3 – 30 mins (24 hours after visit 2) blood samples and PFTs
Visit 4- 10 hours Blood and urine samples, PFTs, FMD measurement, LPS  inhalation and bronchoscopy
Visit 5 – 30 mins (24 hours after visit 4) blood samples and PFTs
Tests / questionnaires that the participants will encounter:
As part of this trial, the participants will undergo blood sampling, measurement of flow mediated dilatation, LPS inhalation and bronchoscopy and bronchoalveolar lavage.
PPI Involvement:
We will also utilise the respiratory support network for the dissemination of results. We will utilise the support group to ensure wide and adequate publicity for the results of this trial which will increase the awareness of patients on the effects of EC vapour on their lungs. There will be wider reach to the public as this will be the first trial to study the in vivo effects of EC vapour on lung inflammation and so will be crucial in guiding future regulations which will impact the wider public.
Who can take part in the Study?:
Inclusion criteria:

1. Healthy subjects less than 45 years of age and BMI < 35

Exclusion criteria:

1. Age < 18 years
2. Pregnant or Breast-Feeding
3. Participation in a clinical trial of an investigational medicinal product within 30 days
4. Consent declined
5. History of asthma
6. Marijuana use or other inhaled products with or without nicotine in the last 3 months
7. Alcohol abuse, as defined by the Alcohol Use Disorders Identification Test (AUDIT)

The three groups in our cohort will be defined as follows and will be used as cohort specific criteria for inclusion into the study:

Electronic Cigarette Users: Subjects who use electronic cigarettes daily and have not used conventional cigarettes in the previous 3 months. Total pack years of smoking should be less than 20 for their smoking history, with normal lung function (FEV1 and FEV1/FVC) and no clinical symptoms of airway obstruction/inflammation (cough, dyspnea, sputum and wheeze).

Cigarette Smokers: Subjects who smoke at least ¼ pack cigarettes per day for the past 1 year, with no history of electronic cigarette use in the last 30 days.

Controls: Subjects with no history of prior conventional cigarette (< 100 cigarettes lifetime) or electronic cigarette use.

Contact Information:
Dr Murali Shyamsundar
Wellcome Wolfson Institute for Experimental Medicine
Lisburn Road, 
Phone number: 02890 976381
Social Media links: not applicable.


NI Clinical Research Facility,
U Floor, Belfast City Hospital,
Lisburn Road, Belfast, BT9 7AB

Tel:+44 (0)28 9504 0342

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