Effects of Chronic Intake of Cannabis on Contrast Sensitivity
2 other identifiers
interventional
95
0 countries
N/A
Brief Summary
Rates of driving under the influence of cannabis have risen in recent years. Cannabis is involved in 1/3 of motor vehicle collisions. The chronic use of cannabis is known to affect dopaminergic regulation and may thus impair contrast sensitivity. In turn, contrast sensitivity disorders could originate difficulties to anticipate and avoid collision with objects, especially when objects are in movement. The investigators goal is to examine the effects of a chronic intake of cannabis on contrast sensitivity. The observed values will be compared to standard references. In addition, since smoking cannabis is always associated with tobacco, the investigators will control the effects of tobacco on contrast sensitivity. In this study, the investigators will include 36 cannabis addicts, 36 tobacco addicts and 36 no smokers. The investigators will present gratings with different spatial frequencies and the investigators will determine contrast thresholds for static and dynamic (moving) gratings. The investigators predict that cannabis addicts will present abnormal contrast sensitivity especially in case of dynamic presentation of gradings.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P50-P75 for not_applicable
Started Mar 2013
Longer than P75 for not_applicable
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
February 12, 2013
CompletedFirst Posted
Study publicly available on registry
February 18, 2013
CompletedStudy Start
First participant enrolled
March 22, 2013
CompletedPrimary Completion
Last participant's last visit for primary outcome
November 30, 2015
CompletedStudy Completion
Last participant's last visit for all outcomes
September 10, 2018
CompletedJuly 12, 2019
July 1, 2019
2.7 years
February 12, 2013
July 10, 2019
Conditions
Outcome Measures
Primary Outcomes (1)
The contrast detection treshold
Comparison of the contrast detection threshold of the 3 groups
up to 9 days after inclusion
Study Arms (3)
"Cannabis" Arm
OTHERpatient addicted to cannabis
"Tobacco" Arm
OTHERpatient addicted to tobacco
"Healthy volunteers"
OTHERno smokers
Interventions
Eligibility Criteria
You may qualify if:
- "Cannabis" Arm
- patient addicted to cannabis
- Positive CAST test result
- Urine tested positive for cannabis metabolites
- "Tobacco" Arm
- positive Fagerström test result
- No previous history of cannabis use
- "Healthy Volunteers"
- No history of addictive disorders
You may not qualify if:
- addiction to other substances than cannabis or tobacco
- benzodiazepine treatment
- patient with history of benzodiazepine treatment
- patient with history of head trauma
- Pregnant woman
- breast feeding woman
- Adults under supervision or guardianship
Contact the study team to confirm eligibility.
Sponsors & Collaborators
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- NON RANDOMIZED
- Masking
- NONE
- Purpose
- OTHER
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
February 12, 2013
First Posted
February 18, 2013
Study Start
March 22, 2013
Primary Completion
November 30, 2015
Study Completion
September 10, 2018
Last Updated
July 12, 2019
Record last verified: 2019-07