Benefits of a Cognitive Behavioral Therapy Intervention for Smoking Cessation Supported by Virtual Reality Smoking Cue Exposure

Study Overview
=================
Brief Summary
-----------------
Cognitive-behavioral therapy (CBT) combined with medication is an established intervention for smoking cessation. However, long-term abstinence rates of maximum 35% are yielded. Moreover, acceptance of drug treatment is partly very low. Professional recommendation of drug treatment besides nicotine-replacement aids is restrained considering side effects and contraindications. Currently, cue exposure is highly discussed as intervention for craving reduction supporting CBT. There is evidence for benefits of cue exposure optimizing smoking cessation outcomes, as well as evidence for efficacy of exposure in virtual reality (VR) up to date. However, this is the first randomized controlled study focusing on efficacy increases by VR cue exposure supporting an established CBT smoking cessation manual. The control group receives a specific stress reduction treatment (independent of smoking cues), namely, the Progressive Muscle Relaxation (PMR, according to Jacobson) additionally to the established smoking cessation CBT.

Official Title
-----------------
An Efficacy Study Using an Established Cognitive Behavioral Therapy Manual for Smoking Cessation Comparing the Benefit of Virtual Reality Cue Exposure to a Specific Stress Reduction Protocol for Relapse Prevention

Conditions
-----------------
Smoking Cessation

Intervention / Treatment
-----------------
* Behavioral: CBT smoking cessation
* Behavioral: virtual reality based cue exposure
* Behavioral: progressive muscle relaxation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: daily smokers for at least 2 years, smoking minimum 10 cigarettes a day Exclusion Criteria: pregnancy current participation in another smoking cessation program within 6 months before assignment current diagnosis of a psychiatric disease including a depression or substance use disorder (excluding nicotine dependency) lifetime diagnosis of a psychiatric disease : psychosis, bipolar affective disorder, posttraumatic stress disorder, conversion disorder.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: VR based cue exposure smoking cessation<br>an established CBT intervention for smoking cessation supported by cue exposure in virtual reality | Behavioral: CBT smoking cessation<br>* an established protocol for smoking cessation based on cognitive behavioral therapy<br>Behavioral: virtual reality based cue exposure<br>* smoking cue exposure in virtual reality<br>|
| Active Comparator: PMR supported smoking cessation<br>an established CBT intervention for smoking cessation supported supported by specific stress reduction (Progressive Muscle Relaxation, Jacobson) | Behavioral: CBT smoking cessation<br>* an established protocol for smoking cessation based on cognitive behavioral therapy<br>Behavioral: progressive muscle relaxation<br>* Progressive muscle relaxation for unspecific stress reduction<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Continuous (self-reported) abstinence rates from smoking 6 months after end of treatment | 6-month continuous smoking abstinence according to the Russell Standard (West et al., 2005): no cigarette smoking assessed by self-report (number of smoked cigarettes) and a negative biochemical validation (CO measurement below 9) at the ﬁnal follow-up. 6-month continuous smoking abstinence ordinal scale: 0=no abstinence, 1= either subjective or biochemical validation depicts no abstinence, 2= biochemical validated abstinence at the 6 months follow-up. | at the 6 month follow-up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in smoking cue event-related potentials (ERP: LPP) | late positive potential (LPP) amplitude (Microvolts) | Differences from baseline to the 6 month follow-up | 
| Changes in smoking cue event-related potentials (ERP:P3) | P3 amplitude (Microvolts) during avoidance of smoking cues | Differences from baseline to the 6 month follow-up | 
| Changes in approach tendency to smoking pictures | Difference in reaction time (ms) bias berween neutral and smoking condition. Approach Bias is calculated as reaction time (ms) difference in avoidance and approach condition. | Differences from baseline to the 6 month follow-up | 
| Changes in smoking cue reactivity related skin conductance level | Differences in conductance level (MicroSiemens) during smoking cue exposure and exposure to a neutral cue. | Differences from baseline to the 6 month follow-up | 
| Changes in Theta and Alpha band power during smoking cue exposure | Differences in Alpha and Theta band power during smoking cue exposure and neutral cue exposure. | Differences from baseline to the 6 month follow-up | 
| Changes in heartbeat-evoked potential during smoking cue exposure | Amplitude (microvolts) of heartbeat-evoked potential | Differences from baseline to the 6 month follow-up | 
| Subjective ratings on the smoking self-efficacy scale | Subjective ratings on on the German version of the self-efficacy scale for smoking cessation (Jäkle et al., 1999) total score for the questionnaire: minium total score (sum): 9 (low self-efficacy, worse outcome), maximum total score= 45 (high self-efficacy, better outcome) | Differences from baseline to the 6 month follow-up | 
| Number of daily smoked cigarettes after smoking cessation | Sum of self-reported smoked cigarettes after smoking cessation | Time Frame: Differences from smoking cessation to the 6 month follow-up | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
virtual reality, cue exposure, progressive muscle relaxation