Clinical trial NCT04325958: Age Differences in the Effects of Cannabis on Simulated Driving
Official title: The Influence of Age on Driving-related Cannabis Effects: Exploring Cannabis Use Frequency and Related Factors
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Cannabis
Lead sponsor: Centre for Addiction and Mental Health
Sponsor class: OTHER
First posted: 2020-03-30
Enrollment: 128
Sex: ALL
Minimum age (years): 19
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Participants will complete a session with active cannabis and a session with placebo cannabis.

Order of sessions is randomized.

Participants and Investigator are blinded.

Allocation to arms is not randomized. Arms are based on their age.
Primary purpose: BASIC_SCIENCE

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.

Eligibility criteria: Inclusion Criteria

* 19-25 or 35-45 years of age;
* Use of smoked cannabis at least once in the past 6 months.
* Use of smoked or vaped cannabis primarily for recreational purposes on up to 1 day per week or on at least 6 days per week in the past 3 months;
* Holds a class G or G2 Ontario driver's licence (or equivalent from another jurisdiction) for at least 12 months;
* Willing to abstain from using alcohol for 24 hours and cannabis for 72 hours prior to Practice and Test Sessions;
* Willing to abstain from all other drugs not prescribed for medical purposes for 48 hours prior to Practice and Test Sessions;
* Resides within Toronto (study site) or can reside with friends/family in Toronto after a Test Session; this area may be extended to the Greater Toronto area if recruitment challenges arise;
* Participant willing to use appropriate contraception until their participation in the study is completed;
* Provides written and informed consent.

Exclusion Criteria

* Use of cannabis primarily for therapeutic purposes, or equally for therapeutic and recreational purposes;
* Diagnosis of medical condition that contraindicates use of cannabis determined by self-report as judged by the Principal Investigator and a study physician; this includes a history of hypersensitivity to cannabinoids smoke, respiratory disease and/or severe cardiovascular, cerebrovascular, renal or liver disease, and bleeding disorders. Smoking cannabis is not recommended for individuals with respiratory diseases, and they will be excluded;
* Diagnosis of psychiatric condition that contraindicates use of cannabis determined by self-report or SCID-5;
* Participants of childbearing potential: Pregnancy (point-of-care test) or breastfeeding;
* Meets criteria for current or lifetime alcohol or other substance use disorder (DSM-5), except tobacco use disorder and caffeine use disorder;
* Is a regular user of medications that affect brain function (based on self-report); this includes concomitant therapy with sedative-hypnotics or other psychoactive drugs
* Use of anti-hypertensives;
* First-degree relative diagnosed with schizophrenia or another psychotic disorder.
* Participation in a past driving study at CAMH (to limit practice effects).
* Participation in a clinical study concurrent with their participation in this study.

Primary outcomes:
measure: Standard deviation of lateral position
timeFrame: Before cannabis exposure and 30 minutes and 2 hours after cannabis exposure
Secondary outcomes:
measure: Mean speed
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure
measure: Standard deviation of speed
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure
measure: Maximum speed
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure
measure: Following distance
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure
measure: Braking latency
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure
measure: Number of collisions
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis exposure
measure: Blood concentration of delta-9-tetrahydrocannabinol (THC)
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis
measure: Blood concentration of carboxy-tetrahydrocannabinol (THC-COOH)
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis
measure: Blood concentration of 11-hydroxy-tetrahydrocannabinol (11-OH-THC)
timeFrame: Before cannabis exposure and 25 minutes and 2 hours after cannabis
measure: Systolic blood pressure
timeFrame: Before cannabis exposure and 5, 15, 25 minutes and 1, 2, 3, 4 and 5 hours after cannabis
measure: Diastolic blood pressure
timeFrame: Before cannabis exposure and 5, 15, 25 minutes and 1, 2, 3, 4 and 5 hours after cannabis
measure: Heart rate
timeFrame: Before cannabis exposure and 5, 15, 25 minutes and 1, 2, 3, 4 and 5 hours after cannabis
measure: Visual Analog Scales such as 'I feel this effect', 'I like this drug effect', 'I feel the good effects'
timeFrame: Before cannabis exposure and 5, 15, 25 minutes and 1, 2, 3, 4 and 5 hours after cannabis
measure: Trail Making Test
timeFrame: Before cannabis exposure and 70 minutes after cannabis
measure: Verbal Free Recall Task
timeFrame: Before cannabis exposure and 70 minutes after cannabis
measure: Grooved Pegboard Test
timeFrame: Before cannabis exposure and 70 minutes after cannabis
measure: Simple and Choice Reaction Time Tasks
timeFrame: Before cannabis exposure and 70 minutes after cannabis
measure: Vienna Risk-Taking Test
timeFrame: One hour after cannabis exposure
Other outcomes:
Locations:
city: Toronto
country: Canada
facility: Centre for Addiction and Mental Health
state: Ontario
Study officials:
affiliation: Centre for Addiction and Mental Health
name: Christine Wickens, PhD
role: PRINCIPAL_INVESTIGATOR
References: