BACKGROUND The aim of this study was to estimate the prevalence of cannabis use among Swiss students and to assess their attitudes regarding health and safety issues associated with drug use. SUBJECTS AND METHODS After a workshop, 173 students (23.1% male, 75.7% female; 44.4% age 16, 43.8% age 17 and 11.8% age 18) from a Swiss school were surveyed by questionnaire. RESULTS 59.3% (n=103) of ...

OBJECTIVE We aimed to assess whether individuals at ultra high risk (UHR) for psychosis have higher rates of cannabis use and cannabis use disorders (CUDs) than non-UHR individuals and determine whether UHR cannabis users have more severe psychotic experiences than non-users. METHOD We conducted a meta-analysis of studies reporting cannabis use in the UHR group and/or positive or negative sym...

The purpose of this article is to identify tobacco and cannabis co-consumptions and consumers' perceptions of each substance. A qualitative research including 22 youths (14 males) aged 15-21 years in seven individual interviews and five focus groups. Discussions were recorded, transcribed verbatim and transferred to Atlas.ti software for narrative analysis. The main consumption mode is cannabis...

BACKGROUND The relationship between cannabis use and psychosis is still a matter for debate. Accounting for the individual differences in subjective experiences to recreational cannabis use in the general population may hold some clues to the aetiological relationship between cannabis and psychotic symptoms. We hypothesized that schizotypy would account for the individual differences in subject...

BACKGROUND The heaviest period of cannabis use coincides with ongoing white matter (WM) maturation. Further, cannabis-related changes may be moderated by FAAH genotype (rs324420). We examined the association between cannabis use and FAAH genotype on frontolimbic WM integrity in adolescents and emerging adults. We then tested whether observed WM abnormalities were linked with depressive or apath...

BACKGROUND Chronic users of cannabis often report withdrawal symptoms after abstinence from use, but little is known about cannabis withdrawal in people with schizophrenia. METHODS Cannabis use patterns and withdrawal symptoms in adults with schizophrenia who had at least weekly cannabis use before attempting to quit without formal treatment were assessed with the Marijuana Quit Questionnaire...

ISSUES To conduct a comprehensive search of the peer-reviewed literature to assess risk of cannabis-related mortality. APPROACH Systematic peer-reviewed literature searches were conducted in Medline, EMBASE and PsycINFO to identify data on mortality associated with cannabis use. Search strings for cannabis and mortality were used. Searches were limited to human subjects and the publication ti...

BACKGROUND Cannabis use is associated with an attention-dependent deficit in prepulse inhibition of the startle reflex (PPI). The aim of the current study was to investigate startle habituation in cannabis users and healthy controls during two attentional tasks. METHODS Auditory startle reflex was recorded from orbicularis oculi muscle while participants (12 controls and 16 regular cannabis u...

BACKGROUND A clearer understanding of the basis for the association between cannabis use and psychotic experiences (PEs) is required. Our aim was to examine the extent to which associations between cannabis and cigarette use and PEs are due to confounding. METHOD A cohort study of 1756 adolescents with data on cannabis use, cigarette use and PEs. RESULTS Cannabis use and cigarette use at ag...

Cannabis is one of the most commonly drugs used by teenagers. Expectancies about its effects play a crucial role in cannabis consumption. Various tools have been used to assess expectancies, mainly self-report questionnaires measuring explicit expectancies, but implicit measures based on experimental tasks have also been developed, measuring implicit expectancies. The aim of this study was to s...