[Cannabis: A Cognitive Illusion]

Cannabis use and dependence among festival attendees: results from the French OCTOPUS survey

BACKGROUND

Chronic use of cannabis is associated with an increased risk of psychosocial, mental and physical health impairments. Sociohealth institutions reach a very limited proportion of cannabis users in need of treatment. Using data collected from festival attendees, this study aimed to estimate the prevalence of dependent cannabis users and to characterize cannabis dependence.

METHODS

We used data from the cross-sectional OCTOPUS survey carried out at 13 music events in the French department of Loire-Atlantique between July 2017 and July 2018. 383 participants aged 18 or older underwent a face-to-face interview about their basic sociodemographics, tobacco use, alcohol use and past-year substance use. Using the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) criteria, we estimated the prevalence of dependent cannabis users and characterized their dependence.

RESULTS

More than two-thirds of participants reported that they had used cannabis in the past 12 months. Among 194 regular cannabis users (at least monthly), 63.4% were dependent. At least 40% of regular users reported health and/or social consequences of cannabis use. Compared to nondependent cannabis users, dependent cannabis users were more likely to be stimulant users and hallucinogen users.

CONCLUSIONS

Dependent cannabis use is common among festival attendees, especially among stimulant or hallucinogen users. Festival settings may be important arenas for i) implementing efficient harm reduction measures to prevent dependence and ii) providing information on care structures and promoting the use of care to dependent users. In addition, healthcare professionals should be aware of trends in polysubstance use among dependent cannabis users.

Adolescents' Cannabis Knowledge and Risk Perception: A Systematic Review

To systematically review evidence evaluating cannabis-related knowledge and perception of risk in children and adolescents. We systematically searched Medline, PsycINFO, and EMBASE using Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. 133 studies from around the world (including ages 10-18 yrs) met inclusion criteria, with 70% meeting grade 2C quality. Increased knowledge and perception of risk of cannabis frequently correlated with lower levels of current use and intent to use. Studies examining correlations over time generally demonstrated increased adolescent cannabis use and decreased perception of risk. Included prevention-based interventions often enhanced knowledge and/or perception of risk in adolescents exposed to the intervention. Studies exploring outcomes relating to legislative changes for recreational marijuana use demonstrated considerable heterogeneity regarding knowledge and perception of risk whereas studies that focused on medicinal marijuana legislative changes overwhelmingly demonstrated a decrease in perception of risk post legalization. Increased knowledge and perception of risk of cannabis in adolescents often correlate with lower levels of current use and intention to use in the future. Further study and implementation of public health and clinically-oriented strategies that seek to increase knowledge among youth about the potential health harms of cannabis use should continue and be prioritized.

Adolescents and youths' opinions about the factors associated with cannabis use: a qualitative study based on the I-Change model

BACKGROUND

To learn about the experiences and opinions of adolescent non-consumers and regular cannabis users about cannabis use and the factors that determine its use, using the I-Change explanatory model as a basis.

METHODS

Qualitative methodology with a content analysis was used. Focus groups were conducted with adolescents who were non-regular cannabis users (those who had not tried cannabis or had only experimented with it before) and semi-structured interviews were conducted with adolescent and young adult in recovery who were in a detoxification program. A deductive analysis of the audio-recorded and transcribed interviews was performed, using the domains of the I-Change Model as a reference.

RESULTS

Personal problems, social problems or family problems can lead to cannabis use. There was a lack of knowledge and low risk perception about consumption of this drug. There are other factors that influence consumption, the perception of advantages, such as the feeling of freedom and the influence of the peer group. The consumption of this substance in girls is changing, becoming more and more equal to that of boys. The family has an important role to play in preventing drug use.

CONCLUSION

Knowledge of these factors is of vital importance as a prior step to the development of efficient intervention measures adjusted to the needs identified and the characteristics of the population.

Assessing the influence of cannabis and alcohol use on different visual functions: A comparative study

This study aimed to assess and compare the influence of alcohol intake and cannabis smoking on different visual functions. A total of 64 young and healthy volunteers took part in the study. All undertook several randomised experimental sessions in which different visual functions, namely distance stereopsis, retinal straylight, visual discrimination capacity, and contrast sensitivity, were tested. Cannabis smokers (N = 30) took a baseline session and a session after smoking a cannabis cigarette, whereas alcohol users (N = 34) underwent a baseline session, a session after a low alcohol intake (Alcohol 1), and a session after a moderate to high alcohol intake (Alcohol 2). All visual functions were impaired by cannabis and alcohol use, particularly for the Cannabis and Alcohol 2 groups. The deterioration of all visual variables was higher for the Alcohol 2 than for the Alcohol 1 and Cannabis groups, except for retinal straylight, the deterioration of which was equal for the Cannabis group, and distant stereopsis, which was more impaired for the Cannabis group. The Alcohol 2 group experienced the most impairing conditions, although very similar to the cannabis group, and that factors other than the experimental conditions, such as sex and age, also influenced these visual changes. Alcohol and cannabis use clearly impair vision. The deterioration caused by cannabis is similar to, but slightly lower than, that produced by a moderate to high alcohol intake, with the experimental conditions, sex and age all having an impact on the variability of visual deterioration.

Comparison of the effects of alcohol and cannabis on visual function and driving performance. Does the visual impairment affect driving?

BACKGROUND

Alcohol and cannabis are the most widely consumed psychoactive substances worldwide. This study compared the effects of alcohol and cannabis on visual function and driving performance, as well as self-perceived effects. Also, the relationship between visual effects under the influence and driving performance was studied.

METHODS

Sixty-four young drivers, with a history of alcohol and/or cannabis use were included. Of these, 33 were allocated to the alcohol group and 31 to the cannabis group. All participants were evaluated in a baseline session. The alcohol group underwent two sessions: after drinking 300 ml and 450 ml of red wine (A1 and A2). The cannabis group attended one session after smoking cannabis (C). Visual function was evaluated at the contrast sensitivity, stereoacuity, and intraocular straylight level. Participants drove a driving simulator. A general score (overall visual score, OVS; overall driving performance score, ODPS) was obtained for both visual functioning and driving performance.

RESULTS

The evaluation of visual function demonstrated a significant impairment in OVS for all conditions studied (A1, p = 0.005; A2, p < 0.001; C, p < 0.001) with respect to the baseline session. General driving performance (ODPS) demonstrated a significant worsening for the A2 condition (p = 0.003). Finally, a significant relationship between driving performance and visual function was found (rho=0.163, p = 0.039 and χ² = 4.801, p = 0.028).

CONCLUSIONS

Cannabis and alcohol use negatively impact visual function. However, driving performance was only significantly affected by the higher alcohol dose. This impairment in visual function was significantly associated with worse driving performance.

Perceptions of the health risks of cannabis: estimates from national surveys in Canada and the United States, 2018-2019

Few studies have compared knowledge of the specific health risks of cannabis across jurisdictions. This study aimed to examine perceptions of the health risks of cannabis in Canada and US states with and without legal non-medical cannabis. Cross-sectional data were collected from the 2018 and 2019 International Cannabis Policy Study online surveys. Respondents aged 16-65 (n = 72 459) were recruited from Nielsen panels using non-probability methods. Respondents completed questions on nine health effects of cannabis (including two 'false' control items). Socio-demographic data were collected. Regression models tested differences in outcomes between jurisdictions and by frequency of cannabis use, adjusting for socio-demographic factors. Across jurisdictions, agreement with statements on the health risks of cannabis was highest for questions on driving after cannabis use (66-80%), use during pregnancy/breastfeeding (61-71%) and addiction (51-62%) and lowest for risk of psychosis and schizophrenia (23-37%). Additionally, 12-18% and 6-7% of respondents agreed with the 'false' assertions that cannabis could cure/prevent cancer and cause diabetes, respectively. Health knowledge was highest among Canadian respondents, followed by US states that had legalized non-medical cannabis and lowest in states that had not legalized non-medical cannabis (P < 0.001). Overall, the findings demonstrate a substantial deficit in knowledge of the health risks of cannabis, particularly among frequent consumers.

Personal Variables of Protection against Cannabis Use in Adolescence: The Roles of Emotional Intelligence, Coping Styles, and Assertiveness as Associated Factors

(1) Background: Many public bodies have warned of the increased consumption of cannabis, particularly among adolescents. From the Positive Youth Development approach, the promotion of personal protective factors takes on special importance against some risks, such as the consumption of addictive substances. (2) Methods: This research is one of the first to study the role of trait and ability emotional intelligence in relation to cannabis use and with respect to other personal variables of protection, such as coping styles and assertiveness. For this purpose, a final sample of 799 schoolchildren was obtained. (3) Results: After controlling for age and gender, the results of the regression analyses revealed that emotional perception, emotional facilitation, emotional clarity, emotional repair, active coping style, and assertiveness were inversely and significantly associated with cannabis use behaviors. On the other hand, the emotional attention and avoidant coping style factors were positively and significantly associated with these behaviors. (4) Conclusions: These findings provide new evidence that could be useful in terms of guiding health-promoting clinical and educational interventions at an early age.

Effects of cannabis on visual function and self-perceived visual quality

Cannabis is one of the most used drugs of abuse in the world. The objective of this study was to analyze the effects of smoking cannabis on vision and to relate these to those perceived by the user. Thirty-one cannabis users participated in this study. Visual function assessment was carried out in a baseline session as well as after smoking cannabis. We evaluated static visual acuity, contrast sensitivity, stereoacuity, accommodative response, straylight, night-vision disturbances (halos) and pupil size. The participants were also divided into two groups depending on whether they perceived their vision to have worsened after smoking cannabis. A logistic regression analysis was employed to identify which visual test could best predict self-perceived visual effects. The study found that smoking cannabis has significant adverse effects on all the visual parameters analyzed (p < 0.05). Self-perceived visual quality results revealed that about two thirds of the sample think that smoking cannabis impairs their vision. Contrast sensitivity, specifically for the spatial frequency 18 cpd, was identified as the only visual parameter significantly associated with self-perceived visual quality (Odds Ratio: 1.135; p = 0.040). Smoking cannabis is associated with negative effects on visual function. Self-perceived visual quality after smoking cannabis could be related to impaired contrast sensitivity.