Modeling Stress-precipitated Vaping Behavior

Study Overview
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Brief Summary
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The primary aims of this pilot study were to (1) initially validate the applicability of a human laboratory model of relapse initially developed for smokers to e-cigarette users; (2) to use this human laboratory model of lapse behavior to examine the effects of acute psychological stress on vaping-lapse behavior among adults who are experienced, e-cigarette users.

Official Title
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Modeling Stress-precipitated Vaping Behavior Among E-Cigarette Users

Conditions
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Vaping

Intervention / Treatment
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* Other: Control task and Trier Social Stress Task


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: at least 18 years old e-cigarette users using ≥1 mL of e-cigarette liquid per day with a nicotine concentration of ≥3mg/ml had used an e-cigarette for at least three months Exclusion Criteria: Current smokers Psychiatric or medical condition based Using a prescription medication other than birth control

Ages Eligible for Study
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Minimum Age: 18 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: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Control task-<br>The Control Task was implemented to ensure the specificity of the psychological stress effects had on study outcomes. Therefore, the Control Task had a similar procedure and the same duration of the TSST, lacking except for only the psychologically stressful component. The control task consisted of (a) Participants had a 5-min a preparation section and anticipation phase (5 min ), (b) a reading task where they had to. Then, all participants had to be read a simple text in a low voice (5 min), and (c) an arithmetic section where they were asked to perform an easy mathematical calculation (5 mins). | Other: Control task and Trier Social Stress Task<br>* Same as Arm<br>|
| Experimental: Experimental Task- Trier Social Stress Task<br>The Trier Social Stress Task (TSST) is a standardized, 15-minute laboratory task designed to induce psychological stress in laboratory settings (Kirschbaum, Pirke, & Hellhammer, 1993). The TSST consists of three continuously successive phases: (a) an anticipation period (5 min); (b) a free speech task (5 min); and (c) a mental arithmetic task (5 min). As is standard in the TSST procedure, participants were told by a research staff member that they would provide a brief speech about their dream job in front of a critical audience. At the end of the speech, a member of the audience instructed the participant to conduct serial subtractions as accurately and quickly as possible. | Other: Control task and Trier Social Stress Task<br>* Same as Arm<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| latency to initiate ad-lib vaping session (in minutes) | Time to vaping during the vaping delay task. Range of time delay is 0 minutes to 50 minutes. | During the two laboratory sessions which occur within 1 week after screening/baseline. | 
| number of puffs purchased and consumed during the self-administration period | Number of e-cigarette uses purchased during the self-administration phase of the vaping delay task. Range of puffs is 0 to 20. | During the two laboratory sessions which occur within 1 week after screening/baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Craving | Craving was measured using a visual analogue scale (VAS) asking How much do you crave an e-cigarette right now? with possible responses ranging from 0 (not at all) to 100 (extremely). | The VAS will be collected at each laboratory session (within 1 week after screening/baseline) 5 times: baseline (pre task), post task (+15 minutes), decision to smoke (+20 minutes), +30 minutes smoking ab-lib, and +60 minutes during smoking ab-lib | 
| Stress | Stress was measured using a visual analogue scale (VAS) asking: How stressed or anxious do you feel right now? with possible responses ranging from 0 (not at all) to 100 (extremely). | The VAS will be collected at each laboratory session (within 1 week after screening/baseline) 5 times: baseline (pre task), post task (+15 minutes), decision to smoke (+20 minutes), +30 minutes smoking ab-lib, and +60 minutes during smoking ab-lib |