Clinical trial NCT03217929: Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) for Food Craving in Obese Individuals.
Official title: Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) for Food Craving in Obese Individuals: a Randomized, Sham-controlled, Double Blind Clinical Trial.
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Obesity
Craving
Keywords: vagus nerve
obesity
craving
food
Lead sponsor: Federal University of São Paulo
Sponsor class: OTHER
First posted: 2017-07-14
Enrollment: 54
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Background: Obesity is one of the most important diseases around the globe; with a continuous increase and public health concern. Current treatments present some limitations. Craving is a symptom usually noticeable and has been described as a "strong desire or urge to use", especially with foods. The vagus nerve and its relations to the neurocircuitry of the reward system play essential roles in food intake regulation and this can be done transcutaneously trough the auricular branch of the vagus nerve (taVNS). Based on the neurobiology of food craving and on the initial data on taVNS demonstrating safety and efficacy in open-label and randomized sham controlled trials, the investigators propose the first randomized, sham controlled, triple-blind trial on taVNS for food craving in obesity.

Methods: This will be a two-arm, triple-blinded, randomized controlled trial with 54 subjects with food craving assigned to either: 1) a 10-session treatment protocol of real taVNS, or 2) a 10-session treatment protocol of sham taVNS, besides qualitative electroencephalogram (qEEG) and heart rate variability (HRV). Participants will be evaluated for primary outcome measures (Food Craving Questionnaire - State \[FCQ-S\] and Food Craving Questionnaire - Trait \[FCQ-T\]) before and after intervention, with a follow-up visit of 30 days after the end of treatment. A comparison between sham and active groups will be performed in three occasions \[baseline (T1), at the end of the stimulation protocol (T2) and 30 days after the last day of stimulation (T3)\].

Discussion: Given the epidemiological situation and economic and social burdens, the possibility of modulating the reward system neurocircuitry trough the vagus nerve with an easy-to-use, low-cost, safe and potential at-home use could represent a breakthrough in treating obesity. The investigators hypothesized that food craving in obese individuals would decrease at least 50%, as well as their intake of high fat, high sugar and processed food, commonly described as palatable foods. Beyond that, the investigators expect that these individuals would improve anxiety symptoms.


Eligibility criteria: Inclusion Criteria:

* Body mass index (BMI)\>29
* Age between 18 and 55 years old
* Food Craving Questionnaire-State and Trait (FCQ-S and FCQ-T)\>108
* Agreement to participate and sign the informed consent term before any procedure is conducted.

Exclusion Criteria:

* History of head injury or epilepsy
* Body metallic implants and pacemaker
* Current use or in the previous six months of psychotropic or anorexigenic medications, recreational drugs and/or participation in weight-loss programs
* Pregnancy or breastfeeding
* Indication of hospitalization
* Substance dependence
* Psychiatric disorder, except for anxiety disorders
* Personality disorders
* Suicidal ideation
* Non-controlled clinical comorbidities.

Primary outcomes:
measure: Reduction of 40% of food craving symptoms
timeFrame: Baseline, at the end of the stimulation protocol (10 days after) and 30 days after the last day of stimulation.
Secondary outcomes:
measure: Decrease of 10% of BMI and hip/waist ratio
timeFrame: Baseline, at the end of the stimulation protocol (10 days after) and 30 days after the last day of stimulation.
measure: Improve metabolic profile.
timeFrame: Baseline, at the end of the stimulation protocol (10 days after) and 30 days after the last day of stimulation.
measure: Improve anxiety symptoms evaluated by the Inventory for Depressive Symptoms (Self-Report version).
timeFrame: Baseline, at the end of the stimulation protocol (10 days after) and 30 days after the last day of stimulation.
Other outcomes:
Locations:
city: São Paulo
country: Brazil
facility: Federal University of São Paulo
Study officials:
affiliation: Federal University of São Paulo
name: Ruth B Grigolon, Master
role: PRINCIPAL_INVESTIGATOR
References: