Puff Biofeedback to Reduce Smoking Reinforcement

Study Overview
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Brief Summary
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The purpose of the study is to examine the effects of a novel bio-behavioral paradigm, entitled, Puff Topography Biofeedback Training, compared to a control condition, in reducing stress-induced smoking reinforcement.

Detailed Description
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Smokers with emotional distress are particularly vulnerable to smoking reinforcement due to various biopsychological factors that contribute to deficits in emotion regulation and heightened reward processing, which undermine cessation efforts. Differences in puffing behavior may correspond with changes in cardiorespiratory parameters that may promote self-regulation and reduce craving. This study is a between-subjects experimental test of Puff Topography Biofeedback Training (PTBT) and its ability to modify puff topography and cardiorespiratory activity during stress-precipitated smoking, and in turn, reduce acute smoking reinforcement. Participants will be randomized to either PTBT or a Control condition and will complete two smoking trials on two successive days. The first smoking trial (Visit 1) will allow participants to gain familiarity with the task. The second smoking trial (Visit 2) will be completed following acute laboratory stress induction (stress-precipitated smoking trial). The primary study aims are to test the effect of PTBT vs. Control as assessed via acute changes in stress-precipitated smoking reinforcement and changes in puffing behavior and cardiorespiratory parameters.The results of this high pre-intervention study could inform the subsequent development of a novel intervention strategy for improving quit outcomes in a treatment-resistant population. The primary study aims are to test the effect of PTBT vs. Control in terms of: (a) objective puff topography parameters; (b) subjective reinforcement; and (c) whether physiological indices reflective of smoking reinforcement differ between conditions.

Official Title
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A Puff Topography Biofeedback Paradigm to Reduce Stress-Precipitated Smoking Reinforcement

Conditions
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Cigarette Smoking

Intervention / Treatment
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* Behavioral: Puff Topography Biofeedback Training
* Behavioral: Control


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-55 Daily smoking ≥ 8 cigarettes/day verified by carbon monoxide analysis of breath sample ≥ 8 ppm Smoking within 30 minutes of waking English fluency. Exclusion Criteria: Current smoking cessation treatment Past-month reduction of cigarettes/day by ≥50% Moderate or severe non-nicotine substance use disorder Past-year psychiatric instability (e.g., psychosis, mania) Severe visual, hearing, or cognitive impairments Medical condition that could impact stress reactivity or physiology Current regular use of medication that could affect cardiorespiratory function (e.g., beta blockers, benzodiazepines; note-use of SSRIs/SNRIs is permitted if dose is stable ≥ 6 wks).

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 55 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: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Control<br>In this condition, participants are instructed to smoke as usual while attending to control stimuli presented to them on a computer monitor. | Behavioral: Control<br>* Visit 1: Participants will be instructed to smoke their usual brand cigarette using the CReSS smoking topography device while passively viewing time-matched control stimulus presented to them on a computer monitor for a duration of five minutes. Visit 2: Participants will be instructed to smoke their cigarette using the CReSS device and instructions provided during Visit 1 after undergoing a brief laboratory stress induction.<br>* Other names: Attention Control;|
| Experimental: Puff Topography Biofeedback Training (PTBT)<br>In this condition, participants are provided instructions on how to puff their cigarette via a computer-assisted paradigm. | Behavioral: Puff Topography Biofeedback Training<br>* Visit 1: Participants will be asked to smoke their usual brand cigarette using the CReSS smoking topography device. Participants will be instructed on how to follow visual and auditory puffing prompts provided to them by a computer program in order to control puffing behavior for a duration of five minutes. Visit 2: Participants will be instructed to smoke their cigarette using the CReSS device and instructions provided during Visit 1 after undergoing a brief laboratory stress induction.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cigarette Purchase Task | The Short-Cigarette Purchase Task (CPT) will be used to assess smoking reinforcement in response to stress-precipitated smoking. The CPT is based on progressive-ratio operant schedules wherein participants self-report their hypothetical cigarette consumption at various levels of price. Hypothetical purchasing will be based on the last cigarette smoked. Five key behavioral economic indices of demand can be obtained from the CPT: intensity (number of cigarettes consumed at zero cost), Omax (peak expenditure for a cigarette), Pmax (price at maximum expenditure for a cigarette), breakpoint (cost whereby consumption is suppressed to zero), and elasticity (the degree to which consumption decreases with increasing price). | Second Training Day following the Stress-Induction and Intervention (Smoking Task) i.e. post intervention, average 1 day. | 
| Modified Cigarette Evaluation Questionnaire | The Modified Cigarette Evaluation Questionnaire (mCEQ) will be used to assess subjective smoking reinforcement. The mCEQ is a self-report measure that assesses how respondents feel about the last cigarette smoked with subscales that index liking (cigarette satisfaction), wanting (craving reduction), and learning (psychological reward). Scores on each of the mCEQ subscales range from 1 to 7. Higher scores on each of the subscales of the mCEQ reflect greater subjective smoking satisfaction, craving reduction, and psychological reward, respectively. Changes in the mCEQ from during Visit 1, to post stress-precipitated smoking, during Visit 2, will be compared. | Second Training Day following the Stress-Induction and Intervention (Smoking Task) i.e. post intervention, average 1 days. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in Cardiac Vagal Control | Continuous electrocardiograph (ECG) and respiration data will be sampled at 1,000Hz during the adaptation period and stress-precipitated smoking periods. Changes in cardiac vagal control will be calculated as the difference in heart rate variability in the high frequency range (i.e., 0.12-0.40 Hz), which reflects parasympathetic control via the vagus nerve. | Second Training Day prior to Stress-Induction, and following Stress-Induction during Intervention (Smoking Task), average 1 day. | 
| Puff topography | Puff topography indices will be objectively measured with the CReSS micro (Plowshare Technologies, Borgwaldt KC, Inc), a hand-held device that has a sterilized flow meter mouthpiece that is connected to a pressure transducer, which converts pressure into a digital signal that is sampled at 1,000Hz. Average Puff duration (sec) will be used to assess mechanism engagement from PTBT. | Second Training Day following Stress-Induction during Intervention (Smoking Task), average 1 day. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Smoking, Cigarette, Stress, Distress