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

Not Applicable

Completed

Brief Summary: 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: 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.

Recruitment & Eligibility

Inclusion Criteria

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

Arm && Interventions

Group	Intervention	Description
Tobacco Cigarette Group	Tobacco Cigarette	This group will not receive an electronic cigarette and will continue to smoke combustible tobacco cigarettes as previously.
Electronic Cigarette Group	Electronic Cigarette	This group will receive an electronic cigarette to use for the duration of the study.

Primary Outcome Measures

Name	Time	Method
Change in overall levels of peripheral inflammatory cytokines	2-8 weeks	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.

Secondary Outcome Measures

Name	Time	Method
Change in BOLD fMRI response to food pictures	2-8 weeks	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.
Change in cotinine levels	2-8 weeks	Change in serum cotinine levels between study visits two and three.
Change in BOLD fMRI response during interoception	2-8 weeks	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.
Frequency of Electronic Cigarette use	2-8 weeks	Daily use of electronic cigarette between study visits two and three.
Frequency of Tobacco Cigarette use	2-8 weeks	Average number of tobacco cigarettes smoked between study visits two and three.
Change in Blood Oxygen Level-Dependent (BOLD) resting state functional connectivity during fMRI	2-8 weeks	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.
Change in exhaled Carbon Monoxide	2-8 weeks	Change in exhaled Carbon Monoxide between study visits two and three.

Locations (1): Laureate Institute for Brain Research
🇺🇸
Tulsa, Oklahoma, United States