Effects of THC and Alcohol on Driving Performance

Study Overview
=================
Brief Summary
-----------------
Low blood concentrations of THC and alcohol appear to have a minimal effect on driving performance.However, there is a gap in the literature about the combined effects of THC and alcohol. There is little empirical evidence to determine whether the combination of THC and alcohol could be additive or multiplicative. This issue is particularly important when dealing with concentrations that are just below legal thresholds - it is important to identify if someone who may have consumed cannabis and alcohol, in quantities that do not exceed legal thresholds, may nonetheless be impaired to drive. Answering this question requires more research on the combined effects of THC and alcohol under tightly controlled experimental conditions. Hence, the purpose of this study is to determine the additive (or multiplicative) effect of standardized low doses of cannabis, in combination with low-doses of alcohol, on a number of outcome measures related to driving. The investigators will focus specifically on the effect of low blood concentrations of THC (0, 125, and 250 µg/kg) alone and in combination with low blood concentrations of alcohol (BAC 0%, .025%, and .049%). They shall determine the combined effect of THC and alcohol on physiological, cognitive, subjective measures of impairment, and simulated driving. This study will focus on younger adults because they have higher impaired driving rates than other age groups. As a secondary aim of the study, the investigators will examine whether previous driving and drug use history are correlated with driving decisions during the simulated drive and subjective measures. This study will contribute to the evidence base informing legislation, policy making, and law enforcement. This study is particularly timely given upcoming changes in legislation about cannabis, and because the combination of THC and alcohol, even below legal thresholds, may lead to impaired driving and crashes.

Official Title
-----------------
Determining the Combined Effects of THC and Alcohol on Driving Performance

Conditions
-----------------
Cannabis, Alcohol Drinking, Accident, Traffic

Intervention / Treatment
-----------------
* Drug: THC 0
* Drug: THC 5
* Drug: THC 10
* Other: BAC 0
* Other: BAC .025
* Other: BAC .049


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: BMI >18 and <30 valid G2 or G Ontario driver's license live on-campus or within 15 minutes drive of campus speak fluent English Exclusion Criteria: history of cardiovascular or psychiatric disorders current use of psychoactive medication current drug or alcohol abuse problem positive drug screen BAC level > .000%

Ages Eligible for Study
-----------------
Minimum Age: 19 Years
Maximum Age: 25 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: THC 0 + BAC 0<br>Participants will receive 0mg of THC in combination with blood alcohol concentrations of .000%. | Drug: THC 0<br>* THC dose = 0mg<br>* Other names: Cannabis;Other: BAC 0<br>* Blood alcohol concentration = .000%<br>|
| Experimental: THC 5 + BAC 0<br>Participants will receive 5mg of THC in combination with blood alcohol concentrations of .000%. | Drug: THC 5<br>* THC dose = 5mg<br>* Other names: Cannabis;Other: BAC 0<br>* Blood alcohol concentration = .000%<br>|
| Experimental: THC 10 + BAC 0<br>Participants will receive 10mg of THC in combination with blood alcohol concentrations of .000%. | Drug: THC 10<br>* THC dose = 10mg<br>* Other names: Cannabis;Other: BAC 0<br>* Blood alcohol concentration = .000%<br>|
| Experimental: THC 5 + BAC .025<br>Participants will receive 5mg of THC in combination with blood alcohol concentrations of .025%. | Drug: THC 5<br>* THC dose = 5mg<br>* Other names: Cannabis;Other: BAC .025<br>* Blood alcohol concentration = .025%<br>|
| Experimental: THC 10 + BAC .025<br>Participants will receive 125 µg/kg of THC in combination with blood alcohol concentrations of .025%. | Drug: THC 5<br>* THC dose = 5mg<br>* Other names: Cannabis;Other: BAC .025<br>* Blood alcohol concentration = .025%<br>|
| Experimental: THC 0 + BAC .049<br>Participants will receive 0 µg/kg of THC in combination with blood alcohol concentrations of .049%. | Drug: THC 0<br>* THC dose = 0mg<br>* Other names: Cannabis;Drug: THC 10<br>* THC dose = 10mg<br>* Other names: Cannabis;Other: BAC .025<br>* Blood alcohol concentration = .025%<br>Other: BAC .049<br>* Blood alcohol concentration = .049%<br>|
| Experimental: THC 5 + BAC .049<br>Participants will receive 5mg of THC in combination with blood alcohol concentrations of .049%. | Drug: THC 5<br>* THC dose = 5mg<br>* Other names: Cannabis;Other: BAC .049<br>* Blood alcohol concentration = .049%<br>|
| Experimental: THC 10 + BAC .049<br>Participants will receive 10mg of THC in combination with blood alcohol concentrations of .049%. | Drug: THC 5<br>* THC dose = 5mg<br>* Other names: Cannabis;Other: BAC .049<br>* Blood alcohol concentration = .049%<br>|
| Experimental: THC 0 + BAC .025<br>Participants will receive 0 µg/kg of THC in combination with blood alcohol concentrations of .025%. | Drug: THC 0<br>* THC dose = 0mg<br>* Other names: Cannabis;Drug: THC 10<br>* THC dose = 10mg<br>* Other names: Cannabis;Other: BAC .025<br>* Blood alcohol concentration = .025%<br>Other: BAC .049<br>* Blood alcohol concentration = .049%<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Demerit Points on Simulated Road Test | Demerit points incurred for driving errors during a simulated a G2 exit exam (the final step in Ontario's graduated licensing framework) on a STISIM Drive 3-screen driving simulator; demerit points will be assigned in real-time by a member of the research team based on the Ontario Ministry of Transportation scoring scheme | @2.5 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Standard Deviation of Lane Position in Meters (STISIM Drive-Recorded Variable) | Recorded by the STISIM simulator during the simulation | @2.5 hours | 
| Mean and Standard Deviation of Velocity in Meters/Second (STISIM Drive-Recorded Variable) | Recorded by the STISIM simulator during the simulation | @2.5 hours | 
| Mean and Standard Deviation of Acceleration in Meters/Second (STISIM Drive-Recorded Variable) | Recorded by the STISIM simulator during the simulation | @2.5 hours | 
| Blood Pressure (Systolic/Diastolic mmHg) | Systolic & diastolic blood pressure via automated blood pressure cuff | @25 minutes and 2 hours | 
| Heart Rate (BPM) & Heart Rate Variability via ECG | Continuous heart rate in beats per minute via 3-lead electrocardiography recording; will allow for calculation of heart rate variability) | Hour 0-3.5 | 
| Electrical Brain Activity via EEG | Continuous brain activity via electroencephalography recording | Hour 0-3.5 | 
| Median Response Time and Efficiency in Alerting, Orienting & Executive Attention as Measured by the Attention Network Test (in milliseconds) | A computerized test to measure participants' performance in three separate components of attention: alerting, orienting, and executive attention | @25 minutes and 2 hours | 
| Perceptual Motor Speed & Efficiency as Measured by Time (in seconds) to Complete Trail Making Tests A&B | A pen and paper test to measure perceptual motor speed and efficiency | @25 minutes and 2 hours | 
| Visual Analogue Scale of Perceived Effects | Ratings of participants' current perceptions of mood and bodily sensations (22 items including anxiety, alertness, dizziness, dry mouth) driving (3 items related to current willingness to drive), and subjective impairment (at time 2 only; 6 items related to strength of effects, perceived performance on tests); all items measures from not at all>extremely or absent>severe on a 100 mm line | @25 minutes and 2 hours | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
THC, Alcohol, Driving, Dronabinol