Measuring THC-induced Cognitive Impairment Using a Mobile Application
Conditions
Brief summary
Marijuana use, for both recreational and therapeutic purposes, is becoming increasingly common as states remove restrictions on use. The increased use raises new concern about the safety of this drug, including its ability to impair basic cognitive and psychomotor tasks, and whether the users are aware of their impairment. We propose to design a simple performance test that users can use in the field, using a cell phone, to assess their level of impairment relative to their own drug-free state. In this preliminary study, we will compare participants' simple task performance after a known dose of delta-9-tetrahydrocannabinol (THC), or placebo, administered under double-blind conditions. In our app the participants will be asked to gauge their own perceived level of impairment (as determined by self-ratings and judgments of impairment) as well as their actual impairment (as gauged by the app), providing important feedback and training about their ability to detect impairment.
Interventions
DRUGDronabinol
THC (Marinol® \[dronabinol\]; Solvay Pharmaceuticals) will be orally administered in doses of 7.5 mg and 15 mg, in opaque capsules with dextrose filler. Placebo capsules contain only dextrose. These doses of THC are known to produce performance impairments as well as subjective intoxication.
DRUGPlacebo
Placebo
Sponsors
University of Chicago
Study design
Allocation
RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes
Inclusion criteria
1. 18-35 years old, males and females (N=44; 36 completers; 18 men, 18 women) 2. BMI 19-26 3. High school education, fluent in English 4. Experienced non-daily marijuana users
Exclusion criteria
5. Current drug/alcohol abuse or dependence 6. Past year drug/alcohol dependence 7. Diagnosis with drug treatment for psychosis/bipolar/schizophrenia 8. Past year major depression 9. Panic/anxiety attacks in past 2 months 10. Post Traumatic Stress Disorder 11. Attention Deficit Hyperactivity Disorder 12. Cardiovascular illness, high blood pressure, abnormal EKG 13. Current medications 14. Pregnant or planning to become pregnant
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Simple Reaction Time | Assessed two hour post intervention at peak effects | In this reaction time task, the user is asked to shake the device in response to a visual clue on the device's screen. The user makes three attempts, in which he or she must shake or move the device with an acceleration that is greater than the value of the thresholdAcceleration property within the given time. The task finishes when the user successfully completes the attempts as instructed in the task. Data collected by this task is in the form of ORKReactionTimeResult objects. Each of these objects contain a timestamp representing the delivery of the stimulus and an ORKFileResult object that references the motion data collected during an attempt. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Placebo Placebo: Placebo | 24 |
| 7.5 mg THC Dronabinol: THC (Marinol® \[dronabinol\]; Solvay Pharmaceuticals) will be orally administered in doses of 7.5 mg and 15 mg, in opaque capsules with dextrose filler. Placebo capsules contain only dextrose. These doses of THC are known to produce performance impairments as well as subjective intoxication (Broyd et al, 2016; Hartman and Huestis, 2013). | 24 |
| 15 mg THC Dronabinol: THC (Marinol® \[dronabinol\]; Solvay Pharmaceuticals) will be orally administered in doses of 7.5 mg and 15 mg, in opaque capsules with dextrose filler. Placebo capsules contain only dextrose. These doses of THC are known to produce performance impairments as well as subjective intoxication (Broyd et al, 2016; Hartman and Huestis, 2013). | 24 |
| Total | 72 |
Baseline characteristics
| Characteristic | Placebo | 7.5 mg THC | 15 mg THC | Total |
|---|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 24 Participants | 24 Participants | 24 Participants | 72 Participants |
| Education - High School Education | 24 Participants | 24 Participants | 24 Participants | 72 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 2 Participants | 2 Participants | 2 Participants | 6 Participants |
| Race (NIH/OMB) Black or African American | 4 Participants | 4 Participants | 4 Participants | 12 Participants |
| Race (NIH/OMB) More than one race | 4 Participants | 4 Participants | 4 Participants | 12 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 2 Participants | 2 Participants | 2 Participants | 6 Participants |
| Race (NIH/OMB) White | 12 Participants | 12 Participants | 12 Participants | 36 Participants |
| Region of Enrollment United States | 24 participants | 24 participants | 24 participants | 72 participants |
| Sex: Female, Male Female | 12 Participants | 12 Participants | 12 Participants | 36 Participants |
| Sex: Female, Male Male | 12 Participants | 12 Participants | 12 Participants | 36 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 24 | 0 / 24 | 0 / 24 |
| other Total, other adverse events | 0 / 24 | 0 / 24 | 0 / 24 |
| serious Total, serious adverse events | 0 / 24 | 0 / 24 | 0 / 24 |
Outcome results
Primary
Simple Reaction Time
In this reaction time task, the user is asked to shake the device in response to a visual clue on the device's screen. The user makes three attempts, in which he or she must shake or move the device with an acceleration that is greater than the value of the thresholdAcceleration property within the given time. The task finishes when the user successfully completes the attempts as instructed in the task. Data collected by this task is in the form of ORKReactionTimeResult objects. Each of these objects contain a timestamp representing the delivery of the stimulus and an ORKFileResult object that references the motion data collected during an attempt.
Time frame: Assessed two hour post intervention at peak effects
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Placebo | Simple Reaction Time | .365 Seconds | Standard Deviation 0.07 |
| 7.5 mg THC | Simple Reaction Time | .386 Seconds | Standard Deviation 0.09 |
| 15 mg THC | Simple Reaction Time | .396 Seconds | Standard Deviation 0.1 |