Impact of Flavors on Nicotine Perception and Self-Administration Via E-cigarettes
Study Details
Study Description
Brief Summary
The goal of this application is to test whether menthol and fruit flavors impact e-cigarette use through dissociable mechanisms and exert their effects differentially across nicotine doses.
Condition or Disease | Intervention/Treatment | Phase |
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Phase 2 |
Detailed Description
This study examines the impact of menthol and fruit flavors on self-administration of e-cigarette solutions containing varying amounts of nicotine. This is a randomized, double-blind study with a within-subject cross-over design, using e-liquids with 5 different flavors and 4 different levels of nicotine for a total of 20 different e-liquid formulations. Each subject will participate in 4 test sessions. The order of flavor and nicotine delivery will be randomized. At each test session, they will undergo directed self-administration, in a randomized order, then an ad libitum self-administration session where they can choose among all of the e-cigarettes used during the directed session. The primary aims assess the impacts of nicotine and flavor (and their interactions) on participants' subjective ratings of the e-liquids during the 'directed' self-administration component, and self-administered puffs during the ad libitum self-administration component. In addition, the study will explore the impact of sex/gender and sensitivity to nicotine aversiveness or bitterness (as operationalized by genetic variations in the alpha-5 subunit of nicotinic acetylcholine receptor that influences the aversive effects of nicotine, or a taste receptor number 38 ( TAS2R38) important for bitterness perception) on study outcomes.
Study Design
Arms and Interventions
Arm | Intervention/Treatment |
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Experimental: E-liquid Order 'A' Order 'A' for E-liquid Self-Administration: All participants will be given all e-liquids (i.e., all 20 nicotine*flavor combinations (4 nicotine* 5 flavor combinations)) in this within-subject, cross-over design study. Participants will be randomized the order in which they self-administer the 20 nicotine*flavor combinations of e-liquid (across and within the 4 visits). The specific order cannot be described here without disrupting the double-blind nature of the study design. |
Drug: Nicotine 0 mg/mL
E-liquid containing no nicotine (0 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 6 mg/mL
E-liquid containing low nicotine (6 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 12 mg/mL
E-liquid containing medium nicotine ( 12 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 24 mg/mL
E-liquid containing high nicotine ( 24 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Other: 'Menthol' flavor
E-liquid containing 'menthol' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Menthol/Mint' flavor
E-liquid containing 'menthol/mint' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Green Apple' flavor
E-liquid containing 'green apple' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Watermelon' flavor
E-liquid containing 'watermelon' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Unflavored'
E-liquid containing no additional flavor (i.e., 'unflavored') will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
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Experimental: E-liquid Order 'B' Order 'B' for E-liquid Self-Administration: All participants will be given all e-liquids (i.e., all 20 nicotine*flavor combinations (4 nicotine* 5 flavor combinations)) in this within-subject, cross-over design study. Participants will be randomized the order in which they self-administer the 20 nicotine*flavor combinations of e-liquid (across and within the 4 visits). The specific order cannot be described here without disrupting the double-blind nature of the study design. |
Drug: Nicotine 0 mg/mL
E-liquid containing no nicotine (0 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 6 mg/mL
E-liquid containing low nicotine (6 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 12 mg/mL
E-liquid containing medium nicotine ( 12 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 24 mg/mL
E-liquid containing high nicotine ( 24 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Other: 'Menthol' flavor
E-liquid containing 'menthol' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Menthol/Mint' flavor
E-liquid containing 'menthol/mint' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Green Apple' flavor
E-liquid containing 'green apple' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Watermelon' flavor
E-liquid containing 'watermelon' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Unflavored'
E-liquid containing no additional flavor (i.e., 'unflavored') will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
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Experimental: E-liquid Order 'C' One nicotine level condition is a medium nicotine e-liquid (12 mg/mL nicotine). All participants will be given all e-liquids (i.e., all 20 nicotine*flavor combinations (4 nicotine* 5 flavor combinations)) in this within-subject, cross-over design study. Participants will be randomized the order in which they self-administer the 20 nicotine*flavor combinations of e-liquid (across and within the 4 visits). The specific order cannot be described here without disrupting the double-blind nature of the study design. |
Drug: Nicotine 0 mg/mL
E-liquid containing no nicotine (0 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 6 mg/mL
E-liquid containing low nicotine (6 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 12 mg/mL
E-liquid containing medium nicotine ( 12 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 24 mg/mL
E-liquid containing high nicotine ( 24 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Other: 'Menthol' flavor
E-liquid containing 'menthol' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Menthol/Mint' flavor
E-liquid containing 'menthol/mint' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Green Apple' flavor
E-liquid containing 'green apple' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Watermelon' flavor
E-liquid containing 'watermelon' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Unflavored'
E-liquid containing no additional flavor (i.e., 'unflavored') will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
|
Experimental: E-liquid Order 'D' One nicotine level condition is a high nicotine e-liquid (24 mg/mL nicotine). All participants will be given all e-liquids (i.e., all 20 nicotine*flavor combinations (4 nicotine* 5 flavor combinations)) in this within-subject, cross-over design study. Participants will be randomized the order in which they self-administer the 20 nicotine*flavor combinations of e-liquid (across and within the 4 visits). The specific order cannot be described here without disrupting the double-blind nature of the study design. |
Drug: Nicotine 0 mg/mL
E-liquid containing no nicotine (0 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 6 mg/mL
E-liquid containing low nicotine (6 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 12 mg/mL
E-liquid containing medium nicotine ( 12 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Drug: Nicotine 24 mg/mL
E-liquid containing high nicotine ( 24 mg/mL nicotine) will be self-administered via e-cigarettes. This will be administered in 5 flavor conditions (1 unflavored, 2 menthol, and 2 fruit conditions).
Other Names:
Other: 'Menthol' flavor
E-liquid containing 'menthol' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Menthol/Mint' flavor
E-liquid containing 'menthol/mint' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Green Apple' flavor
E-liquid containing 'green apple' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Watermelon' flavor
E-liquid containing 'watermelon' flavor will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
Other: 'Unflavored'
E-liquid containing no additional flavor (i.e., 'unflavored') will be self-administered via e-cigarettes. This will be administered in 4 nicotine conditions (0, 6, 12, 24 mg/mL nicotine).
Other Names:
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Outcome Measures
Primary Outcome Measures
- Subjective drug ratings [immediately after intervention]
Subjective ratings of e-liquids delivered via e-cigarette will be assessed during the 'directed' self-administration component of each test day, using visual analogue scales (VAS). VAS scores range from 0=not at all to 100=extremely. Separate VAS scales will be collected for subjective ratings of aversive properties (higher scores reflect more aversiveness) and rewarding properties (higher scores reflect more rewarding properties) of the e-cigarettes, in each nicotine*flavor condition. Subjective drug ratings for each nicotine*flavor condition will be tested at one test day only and the order of nicotine*flavor conditions will be randomized across the test days (and order within test days will be randomized).
- E-cigarette use [immediately after intervention]
Number of puffs from each e-cigarette (containing different e-liquids) will be measured during the ad libitum self-administration component of each test day. E-cigarette use (ad libitum puffs) for each nicotine*flavor condition will be tested at one test day only and the order of nicotine*flavor conditions will be randomized across the test days (and order within test days will be randomized).
Eligibility Criteria
Criteria
Inclusion Criteria:
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Past month daily cigarette, nicotine-containing e-cigarette, and/or cigar/little cigar/cigarillo use.
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Urine cotinine levels consistent with regular nicotine use
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For women, using acceptable birth control methods
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Able to read and write English
Exclusion Criteria:
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Current or history of major medical illness psychiatric diagnosis or substance use or psychotropic medication use that the physician investigator deems a contraindication for study participation
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Current psychiatric diagnosis of bipolar affective disorder, schizophrenia, homicidal or suicidal ideation
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Any allergy to propylene glycol, vegetable glycerin, menthol, mint, green apple or watermelon flavorants
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For women, pregnant as determined by pregnancy screening, or breast feeding
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Seeking (or undergoing) treatment for nicotine dependence or smoking
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Inability/unwillingness to fulfill scheduled visits and procedures including directed self-administration of all e-liquid flavors
Contacts and Locations
Locations
Site | City | State | Country | Postal Code | |
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1 | Yale University School of Medicine | New Haven | Connecticut | United States | 06511 |
Sponsors and Collaborators
- Yale University
- National Institute on Drug Abuse (NIDA)
Investigators
- Principal Investigator: Elise DeVito, PhD, Yale University
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 2000029704
- R01DA046360
- 2000025408