Clinical trial NCT03555968: Effects of THC and Alcohol on Driving Performance
Official title: Determining the Combined Effects of THC and Alcohol on Driving Performance
Study type: INTERVENTIONAL
Overall status: WITHDRAWN
Phase: PHASE4
Conditions: Cannabis
Alcohol Drinking
Accident, Traffic
Keywords: THC
Alcohol
Driving
Dronabinol
Lead sponsor: Lakehead University
Sponsor class: OTHER
First posted: 2018-06-14
Enrollment: 0
Sex: ALL
Minimum age (years): 19
Maximum age (years): 25
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: FACTORIAL
Primary purpose: BASIC_SCIENCE

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.


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%

Primary outcomes:
measure: Demerit Points on Simulated Road Test
timeFrame: @2.5 hours
Secondary outcomes:
measure: Standard Deviation of Lane Position in Meters (STISIM Drive-Recorded Variable)
timeFrame: @2.5 hours
measure: Mean and Standard Deviation of Velocity in Meters/Second (STISIM Drive-Recorded Variable)
timeFrame: @2.5 hours
measure: Mean and Standard Deviation of Acceleration in Meters/Second (STISIM Drive-Recorded Variable)
timeFrame: @2.5 hours
measure: Blood Pressure (Systolic/Diastolic mmHg)
timeFrame: @25 minutes and 2 hours
measure: Heart Rate (BPM) & Heart Rate Variability via ECG
timeFrame: Hour 0-3.5
measure: Electrical Brain Activity via EEG
timeFrame: Hour 0-3.5
measure: Median Response Time and Efficiency in Alerting, Orienting & Executive Attention as Measured by the Attention Network Test (in milliseconds)
timeFrame: @25 minutes and 2 hours
measure: Perceptual Motor Speed & Efficiency as Measured by Time (in seconds) to Complete Trail Making Tests A&B
timeFrame: @25 minutes and 2 hours
measure: Visual Analogue Scale of Perceived Effects
timeFrame: @25 minutes and 2 hours
Other outcomes:
Locations:
Study officials:
affiliation: Lakehead University
name: Michel Bédard, PhD
role: PRINCIPAL_INVESTIGATOR
References: