Clinical trial NCT02983773: Marijuana's Impact on Alcohol Motivation and Consumption
Official title: Marijuana's Impact on Alcohol Motivation and Consumption
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
Conditions: Alcohol Drinking
Marijuana
Lead sponsor: Brown University
Sponsor class: OTHER
Collaborators: name: National Institute on Alcohol Abuse and Alcoholism (NIAAA)
First posted: 2016-12-06
Enrollment: 131
Sex: ALL
Minimum age (years): 21
Maximum age (years): 44
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: BASIC_SCIENCE

Brief summary: This laboratory study will employ a repeated measures experimental design to examine the effect of high (7.2% THC) and moderate (3% THC) dose of marijuana, relative to placebo, on alcohol craving and on behavioral economic measure of alcohol demand after exposure to alcohol cues, and on subsequent drinking in an alcohol choice task in which participants choose either to drink or receive monetary reinforcement for drinks not consume. The study will recruit 173 non-treatment seeking heavy episodic alcohol drinkers who smoke marijuana at least twice weekly.

Detailed description: This laboratory study will employ a repeated measures experimental design to examine the effect of high (7.2% THC) and moderate (3.0% THC) dose of marijuana, relative to placebo, on alcohol craving and on behavioral economic measure of alcohol demand after exposure to alcohol cues, and on subsequent drinking in an alcohol choice task in which participants choose either to drink or receive monetary reinforcement for drinks not consumed. Moderators of the marijuana's effects on alcohol-related dependent variables will be tested: DSM5 alcohol use disorder severity, affective vulnerability, trait impulsivity, and working memory functioning. Several empirically-determined mechanisms that may explain why marijuana may increase risk of alcohol relapse and help maintain heavy drinking will be tested as mediators of marijuana's effects on alcohol. The study will recruit 173 non-treatment seeking heavy episodic alcohol drinkers who smoke marijuana at least twice weekly to obtain the final sample of 150 with complete data (15% of attrition). Participants will be tested at a baseline session and during three experimental sessions. Investigators will collect blood samples for analysis of cannabinoid plasma levels and to examine marijuana-induced changes in hormones and other biomarkers potentially related to appetite, inflammation and stress. Collection of these biomarkers would allow for a greater understanding about the mechanisms whereby marijuana may acutely increase alcohol motivation and use. The findings will inform researchers and clinicians about how marijuana acutely increases alcohol craving and consumption. The strategy of this proposal is to use the most comprehensive controlled test characterizing marijuana's putative effects on alcohol.

Eligibility criteria: Inclusion Criteria:

* Age 21 to 44
* English-speaking
* marijuana smoking in past month
* report of current heavy episodic (binge) drinking
* in good physical health and weighing \< 250 lbs
* zero breath alcohol at each visit

Exclusion Criteria:

* history of seizures
* smoking \>20 tobacco cigarettes per day
* positive pregnancy test
* nursing
* positive urine toxicology screen for drugs other than cannabis
* interest to quit or receive treatment for marijuana or alcohol use
* meeting criteria for a current affective disorder (depression, or mania, panic disorder, and having psychotic symptoms as assessed by the SCID)

Primary outcomes:
measure: change in alcohol craving
timeFrame: T1: pre-smoking (-45 minutes) and post smoking at 20 (T2), 55 (T3), and 70 (T4) minutes for a total of two hours during the experimental session
Secondary outcomes:
measure: change in alcohol demand measured with Alcohol Purchase Task-State Version (APT-SV)
timeFrame: T1: pre-smoking (-45 minutes) and post smoking at 55 (T2) and 70 (T3) minutes for a total of two hours during the experimental session
measure: number of alcohol beverages consumed
timeFrame: post-smoking during two-hour alcohol choice task during the experimental session
Other outcomes:
Locations:
city: Providence
country: United States
facility: Brown University
state: Rhode Island
Study officials:
affiliation: Brown University
name: Jane Metrik, PhD
role: PRINCIPAL_INVESTIGATOR
References: