The Impact of Waterpipe Tobacco Flavors on Waterpipe Smoking Intentions, Perceptions, Patterns, and Toxicant Exposure

Study Overview
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Brief Summary
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The overall aim of the current study is to determine if flavorings contribute to the initiation and maintenance of waterpipe (WP) smoking and also influence how a WP is smoked, which has implications for both risk of dependence but also smokers' level of exposure to tobacco-related toxicants. A total of 94 current WP smokers (47 low dependent, 47 high dependent) will be recruited. Based on our team's previous studies we conservatively assume a 20% attrition rate; thus, we will need to recruit 94 participants to have 76 complete all four sessions. Consistent with other laboratory studies of waterpipe smoking, participants who meet the following eligibility criteria will be asked to take part in the study.

Detailed Description
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After completing the initial screening by phone, participants will be informed of the study procedures and invited to the lab to complete three WP smoking sessions. Participants will perform exhaled carbon monoxide testing (eCO< 10ppm) and confirm that they have not used any nicotine/tobacco/marijuana products over the last 12 hours. Pregnancy exclusion will also be confirmed with a urine test, and pregnancy tests will be completed at each visit throughout the study. Participants will be randomized and complete study procedures in self-selected dyads. The sessions will be counterbalanced and include: 1) smoking preferred flavored-sweetened WP tobacco, 2) smoking unflavored-sweetened WP tobacco, and 3) smoking unflavored-very low sweetened WP tobacco. Participants will complete all three study visits in the laboratory. Pre-session abstinence from tobacco for at least 12 hours will be mandatory for all participants. Abstinence will be confirmed via participant self-report and an exhaled carbon monoxide monitor (< 20 ppm) for tobacco use. Participant dyads will smoke hookah ad libitum for up to 1 hour. This procedure will be completed for all visits. Participants will also complete a minimum 48-hour washout period between sessions. Participants will not be allowed to eat, drink or use their phone during the session. Initially, one piece of charcoal will be lit and placed on top of the foil. Our preliminary studies, as well as other WP laboratory trials, indicate that one piece of charcoal will not be sufficient for one WP session; thus, participants will be provided additional pre-weighed pieces to use as they wish. Use of additional charcoal will be recorded. Participants will smoke ad libitum and a WP puff topography device will discretely record smoking behavior throughout the session, including puff duration, number of puffs, puff volume, puff flow rate, and time between puffs. Blood samples (15mL per sample) and eCO will be collected immediately pre- and post-waterpipe session. Self-report measures will be administered.

Official Title
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The Impact of Waterpipe Tobacco Flavors on Waterpipe Smoking Intentions, Perceptions, Patterns, and Toxicant Exposure

Conditions
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Smoking, Hookah, Waterpipe Smoking

Intervention / Treatment
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* Behavioral: Flavored-Sweetened Waterpipe Tobacco
* Behavioral: Unflavored-sweetened waterpipe tobacco
* Behavioral: Unflavored-very low sweetened waterpipe tobacco
* Behavioral: Flavored-very low sweetened waterpipe


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: current water pipe smoker for at least the past 6 months smoke water pipe at least 3 times in the last 6 months Lebanese Waterpipe Dependence Scale-11 (LWDS-11) score of ≤9 (Low Dependence) or ≥10 (High Dependence) between 18-50 years old willing to provide informed consent abstain from all tobacco, nicotine, and marijuana use for at least 12 hours prior to each of the three sessions Exclusion Criteria: self-reported diagnosis of lung disease including asthma, cystic fibrosis, or chronic obstructive pulmonary disease currently pregnant, planning to become pregnant, or breastfeeding history of cardiac event or distress within the last 3 months any use of other illicit drugs during the last 30 days.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 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: Health Services Research
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Flavored-sweetened<br>Flavored-sweetened (FS) WP tobacco will be associated with longer and more frequent puffing resulting in the greatest overall levels of smoke inhalation (mL of smoke inhaled), highest abuse potential, and greatest levels of exposure to nicotine and carbon monoxide (CO). , followed by unflavored-sweetened WP, and lastly unflavored-very low sweetened WP. (H1d) A majority of WP smokers will report having initiated WP smoking with flavored-sweetened tobacco and report flavoring as an important reason for trying WP. | Behavioral: Flavored-Sweetened Waterpipe Tobacco<br>* Pre-weighed flavored-sweetened waterpipe tobacco will be prepared.<br>|
| Active Comparator: Unflavored-sweetened<br>Unflavored-sweetened (US) WP will be associated with the second longest and slightly less frequent puffing than FS resulting in the second greatest overall levels of smoke inhalation (mL of smoke inhaled), abuse potential, and levels of exposure to nicotine and carbon monoxide (CO). | Behavioral: Unflavored-sweetened waterpipe tobacco<br>* Pre-weighed unflavored-sweetened waterpipe tobacco will be prepared.<br>|
| Active Comparator: Unflavored very low sweetened<br>Unflavored-very low sweetened (UU) WP will be associated with the shortest and the least frequent puffing resulting in the least overall levels of smoke inhalation (mL of smoke inhaled), abuse potential, and levels of exposure to nicotine and carbon monoxide (CO). | Behavioral: Unflavored-very low sweetened waterpipe tobacco<br>* Pre-weighed unflavored-very low sweetened waterpipe tobacco will be prepared.<br>|
| Active Comparator: Flavored-very low sweetened waterpipe<br>Flavored-very low sweetened WP will be associated with the third longest and slightly less frequent puffing than US resulting in the third greatest overall levels of smoke inhalation (mL of smoke inhaled), abuse potential, and levels of exposure to nicotine and carbon monoxide (CO). | Behavioral: Flavored-very low sweetened waterpipe<br>* Pre-weighed flavored-very low sweetened waterpipe tobacco will be prepared.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Level of Smoke Inhalation Measured by Topography Device | Participants will complete one ad-lib puffing session at each visit. Levels of smoke inhalation will be measured throughout each ad-lib puffing session. Flavored-sweetened WP tobacco will be associated with longer and more frequent puffing resulting in the greatest overall levels of smoke inhalation (mL of smoke inhaled). | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Levels of Smoke Inhalation Between High vs. Low Dependent WP | Waterpipe dependence for participants will be determined at baseline. Participants will complete one ad-lib puffing session at each visit. Levels of smoke inhalation will be measured throughout each ad-lib puffing session. Flavored-sweetened WP tobacco will be associated with longer and more frequent puffing resulting in the greatest overall levels of smoke inhalation (mL of smoke inhaled). Compared to high dependence users smoking unflavored WP tobacco, low dependence users will show greater declines in (H2a) puff frequency and duration resulting in lower levels of smoke inhalation | 6 months |