Age Differences in the Effects of Cannabis on Simulated Driving
- Registration Number
- NCT04325958
- Lead Sponsor
- Centre for Addiction and Mental Health
- Brief Summary
Epidemiological studies suggest that the use of cannabis is associated with an increase in the risk of motor vehicle collisions. It is also known that younger users may be at increased risk for motor vehicle collisions. Further, the frequency with which cannabis is used may be an important variable in determining the effects of cannabis on driving. The purpose of the present study will be to investigate the effects of cannabis on simulated driving in young as compared to middle-aged drivers. Half of the participants will be occasional users of cannabis and half will be frequent users of cannabis.
- Detailed Description
Epidemiological studies have established that the use of cannabis can increase the risk of a motor vehicle collision. A number of variables can influence the effects of cannabis on driving. For example, frequent users of cannabis have been shown to have different cognitive and physiological responses to cannabis as compared to occasional users. In addition, we know that younger drivers are more likely to be involved in motor vehicle collisions after alcohol use as compared to older users. The contribution of age and experience with cannabis on cannabis-mediated effects on driving have yet to be delineated in laboratory studies. The purpose of the present investigation will be to determine whether cannabis has different effects on driving in young, as compared to middle aged, drivers. Half of each age group will be occasional users of cannabis and the other half will be frequent users.
Eligible participants will attend the laboratory for two test sessions; in one session they will smoke a cannabis cigarette and in the other they smoke a placebo cigarette. Participants will drive a driving simulator before and after smoking the cigarette. Blood for measurement of THC and metabolites will also be collected before smoking the cigarette and at a number of times after smoking. Subjective and cognitive tasks will be completed before and after smoking.
It is hoped that the findings of this study will help to inform public perception and policy into the potential effects of cannabis on driving.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- All
- Target Recruitment
- 128
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- CROSSOVER
- Arm && Interventions
Group Intervention Description Age group 35 to 45 Placebos Participants will complete two sessions: one where they drive the simulator before and after smoking a placebo cannabis cigarette (\<1% THC), the other where they drive the simulator before and after smoking an active cannabis cigarette (15% ± 5% THC). Age group 19 to 25 Placebos Participants will complete two sessions: one where they drive the simulator before and after smoking a placebo cannabis cigarette (\<1% THC), the other where they drive the simulator before and after smoking an active cannabis cigarette (15% ± 5% THC). Age group 35 to 45 Cannabis Participants will complete two sessions: one where they drive the simulator before and after smoking a placebo cannabis cigarette (\<1% THC), the other where they drive the simulator before and after smoking an active cannabis cigarette (15% ± 5% THC). Age group 19 to 25 Cannabis Participants will complete two sessions: one where they drive the simulator before and after smoking a placebo cannabis cigarette (\<1% THC), the other where they drive the simulator before and after smoking an active cannabis cigarette (15% ± 5% THC).
- Primary Outcome Measures
Name Time Method Standard deviation of lateral position Before cannabis exposure and 30 minutes and 2 hours after cannabis exposure A measure of 'weaving' when driving the simulator (meters)
- Secondary Outcome Measures
Name Time Method Maximum speed Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure A measure of the greatest speed obtained while driving the simulator (in km/hr)
Braking latency Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure A measure of the time it takes to move the foot from the gas pedal to the brake when a stop sign is encountered (seconds)
Number of collisions Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure The number of collisions while driving the simulator (total number)
Trail Making Test Before cannabis exposure and 70 minutes after cannabis A measure of the cognitive effects of cannabis (performance speed in seconds)
Vienna Risk-Taking Test One hour after cannabis exposure A measure of the amount of risk-taking (latency)
Systolic blood pressure Before cannabis exposure and 5, 15, 25 minutes and 1, 2, 3, 4 and 5 hours after cannabis A vital sign (mmHg)
Following distance Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure A measure of the distance between the car being driven and the car in front (meters)
Diastolic blood pressure Before cannabis exposure and 5, 15, 25 minutes and 1, 2, 3, 4 and 5 hours after cannabis A vital sign (mmHg)
Mean speed Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure A measure of the average speed while driving the simulator (km/hr)
Standard deviation of speed Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure A measure of the variability in speed while driving the simulator (km/hr)
Heart rate Before cannabis exposure and 5, 15, 25 minutes and 1, 2, 3, 4 and 5 hours after cannabis A vital sign (beats/minute)
Visual Analog Scales such as 'I feel this effect', 'I like this drug effect', 'I feel the good effects' Before cannabis exposure and 5, 15, 25 minutes and 1, 2, 3, 4 and 5 hours after cannabis A measure of the subjective effects of cannabis (on a scale of 0 to 100, where is 100 is the strongest level of agreement)
Blood concentration of delta-9-tetrahydrocannabinol (THC) Before cannabis exposure and 25 minutes and 2 hours after cannabis A measure of the psychoactive component of cannabis in blood (ng/ml)
Blood concentration of carboxy-tetrahydrocannabinol (THC-COOH) Before cannabis exposure and 25 minutes and 2 hours after cannabis A measure of the inactive metabolite of cannabis in blood (ng/ml)
Blood concentration of 11-hydroxy-tetrahydrocannabinol (11-OH-THC) Before cannabis exposure and 25 minutes and 2 hours after cannabis A measure of the active metabolite of cannabis in blood (ng/ml)
Verbal Free Recall Task Before cannabis exposure and 70 minutes after cannabis A measure of the cognitive effects of cannabis (number correct)
Grooved Pegboard Test Before cannabis exposure and 70 minutes after cannabis A measure of the cognitive effects of cannabis (performance speed in milliseconds)
Simple and Choice Reaction Time Tasks Before cannabis exposure and 70 minutes after cannabis A measure of the cognitive effects of cannabis (milliseconds)
Trial Locations
- Locations (1)
Centre for Addiction and Mental Health
🇨🇦Toronto, Ontario, Canada