TNS for Treating Nicotine Craving

Study Overview
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Brief Summary
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Electrical stimulation provides direct modulatory effects on subcortical regions. Indeed, neuroimaging studies show changes in neural activity in specific brain regions such as the amygdala, insula, precentral gyrus, hippocampus and thalamus. The neuroanatomical connections established with the trigeminal nerve have been associated with the mechanism called bottom-up neuromodulation. According to this hypothesis, the spread of electrical stimulation follows a path from the peripheral nerves towards the brain stem was then advertise for cortical and subcortical regions. Connections to structures involved in the reward system as the amygdala and hippocampus could theoretically modulate dysfunctional brain activity in these regions, which may induce favorable clinical effects.

Official Title
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Effect of Trigeminal Nerve Stimulation (TNS) on Nicotine Craving: Phase II, Cross-over, Randomized, Sham-controlled Clinical Trial

Conditions
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Nicotine Craving

Intervention / Treatment
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* Device: TRIGEMINAL NERVE STIMULATION (TNS)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients over 18 years both genres diagnosed with nicotine related disorder for at least 12 months according to the diagnostic criteria of DSM-IV administered by a psychiatrist. Also we will adopt as inclusion criteria a score of Nicotine Dependence Fagerstrom Test greater or equal to 5 points. Finally, patients should be able to read and understand the portuguese language. Patients will be selected from spontaneous demand. In accordance to informed consent - Exclusion Criteria: other psychiatric diagnosis such as bipolar Affective Disorder, alcohol dependence, schizophrenia and dementia. Also excluded patients with severe neurological or medical diseases, such as neurodegenerative diseases, stroke, cancer in activity, congestive heart failure or chronic obstructive pulmonary disease stage III or IV. Finally, patients with severe suicidal ideation (structured planning suicide or attempted suicide in the past 4 weeks) will be excluded. In this case, the patient will be seen immediately by a psychiatrist of the research itself that will take the appropriate clinical management according to the severity of suicidal thinking. -

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 69 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: TNS-active<br>TRIGEMINAL NERVE STIMULATION (TNS) | Device: TRIGEMINAL NERVE STIMULATION (TNS)<br>* TNS stimulation over V1 branches of V cranial nerve. Single session for 30 minutes. The patient will undergo a specific cue-induced cigarette craving model during the final 3 minutes of stimulation. Craving scores will be rated before and after stimulation<br>* Other names: TNS;|
| Placebo Comparator: TNS-sham<br>TRIGEMINAL NERVE STIMULATION (TNS) - sham | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Craving for nicotine | Craving for nicotine assessed by visual scale before and after cue-induced images for nicotine craving. Patients will be exposed to visual model for cue-induced images related to nicotine craving during the last 3 minutes of the TNS protocol (which has an overall time of 30 minutes). Main comparison will be between T1 and T2 craving level. | (T1) Immediately before TNS protocol ; (T2) 30 minutes after TNS protocol |