Neurophysiological and Immunological Effects of the Transition From Combustible to Electronic Cigarettes

Study Overview
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Brief Summary
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The objective of this study is to examine the cognitive, immunological, and neurophysiological effects of transitioning from tobacco cigarettes to electronic cigarettes. The central hypothesis of this study is that this transition will be accompanied by a decrease in peripheral inflammation, which will lead to significant changes in the neurocircuitry underlying interoception and appetite.

Detailed Description
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Participants who are current cigarette smokers will be randomly assigned to either the experimental or control groups. Following a baseline psychiatric assessment session, subjects will return to the study center for two to three additional follow-up visits. During the second visit, all subjects will undergo a functional magnetic resonance imaging (fMRI) scanning session, during which they will perform a series of functional neuroimaging tasks designed to examine the neural substrates involved in visceral interoception and eating behavior. Prior to the start of the scan session, blood samples will be collected from each subject, for the measurement of bio-markers related to nicotine use and peripheral inflammation. After the end of the second visit, subjects within the experimental group will be asked to switch from combustible to electronic cigarettes. Subjects within the control group will continue to smoke combustible cigarettes as previously. During the third visit, which will follow two to eight weeks after the second visit, all subjects will provide a second blood sample and complete a second fMRI scan session. Both groups of participants will complete the same fMRI tasks as they did during the second visit.

Official Title
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Neurophysiological and Immunological Effects of the Transition From Combustible to Electronic Cigarettes

Conditions
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Tobacco Smoking, Nicotine Dependence

Intervention / Treatment
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* Other: Electronic Cigarette
* Other: Tobacco Cigarette


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: current cigarette smokers who have smoked for at least one year right-handed adults able to provide written informed consent Exclusion Criteria: use of anticonvulsant, stimulant, or antipsychotic medication for 3 weeks prior to scanning any medical conditions or medications likely to influence cerebral blood flow or neurological function including cardiovascular, respiratory, endocrine and neurological diseases any history of drug (other than nicotine) or alcohol abuse within 1 year current pregnancy or breast feeding primary language other than English meeting general MRI exclusion criteria such as magnetic implants or claustrophobia Past history of any axis I psychiatric condition, other than major depressive disorder and post-traumatic stress disorder Current major depression or post-traumatic stress disorder Serious suicidal ideation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Tobacco Cigarette Group<br>This group will not receive an electronic cigarette and will continue to smoke combustible tobacco cigarettes as previously. | Other: Tobacco Cigarette<br>* Smoke own brand of cigarette as previously<br>|
| Experimental: Electronic Cigarette Group<br>This group will receive an electronic cigarette to use for the duration of the study. | Other: Electronic Cigarette<br>* eGo-type electronic cigarette with a supply of 18mg/ml nicotine solution<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in overall levels of peripheral inflammatory cytokines | A composite measure of change in overall blood serum levels of multiple peripheral cytokines (CRP, TNF-alpha, sVCAM, IL-1RA, IL-6) between study visits two and three. | 2-8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in cotinine levels | Change in serum cotinine levels between study visits two and three. | 2-8 weeks | 
| Frequency of Electronic Cigarette use | Daily use of electronic cigarette between study visits two and three. | 2-8 weeks | 
| Change in exhaled Carbon Monoxide | Change in exhaled Carbon Monoxide between study visits two and three. | 2-8 weeks | 
| Frequency of Tobacco Cigarette use | Average number of tobacco cigarettes smoked between study visits two and three. | 2-8 weeks | 
| Change in Blood Oxygen Level-Dependent (BOLD) resting state functional connectivity during fMRI | Difference in resting-state functional connectivity between brain regions, measured by z-scores of correlated spontaneous fluctuations of the BOLD fMRI signal, between study visits two and three. | 2-8 weeks | 
| Change in BOLD fMRI response during interoception | Difference in the brain's hemodynamic response during a task of interoceptive attention to visceral signals, measured by percent change of the BOLD fMRI signal, between study visits two and three. | 2-8 weeks | 
| Change in BOLD fMRI response to food pictures | Difference in the brain's hemodynamic response to viewing pictures of appetizing food, measured by percent change of the BOLD fMRI signal, between study visits two and three. | 2-8 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Electronic Cigarette