Biomaterial Database

Cannabis-induced psychosis-like experiences are associated with high schizotypy. 2006

E J Barkus, and J Stirling, and R S Hopkins, and S Lewis

Neuroscience and Psychiatry Unit, University of Manchester, Manchester, UK. emma.j.barkus@manchester.ac.uk

OBJECTIVE Recent studies have suggested that cannabis use is a risk factor for developing schizophrenia. We tested the hypothesis that cannabis use increases the likelihood of psychosis-like experiences in non-clinical participants who scored highly on a measure of schizotypy. METHODS The psychological effects of cannabis were assessed in 137 healthy individuals (76% female, mean age 22 years) using a newly developed questionnaire concerned with subjective experiences of the drug: the Cannabis Experiences Questionnaire. The questionnaire has three subscales: Pleasurable Experiences, Psychosis-Like Experiences and After-Effects. Respondents also completed the brief Schizotypal Personality Questionnaire. RESULTS Cannabis use was reported by 72% of the sample. Use per se was not significantly related to schizotypy. However, high scoring schizotypes were more likely to report both psychosis-like experiences and unpleasant after-effects associated with cannabis use. The pleasurable effects of cannabis use were not related to schizotypy score. CONCLUSIONS High scoring schizotypes who use cannabis are more likely to experience psychosis-like phenomena at the time of use, and unpleasant after-effects. Our results are consistent with the hypothesis that cannabis use is a risk factor for full psychosis in this group.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008385	Marijuana Smoking	Inhaling and exhaling SMOKE from CANNABIS.	Cannabis Smoking,Hashish Smoking,Marihuana Smoking,Smoking Blunts,Smoking, Blunts,Blunt, Smoking,Blunts Smoking,Blunts Smokings,Blunts, Smoking,Smoking Blunt,Smoking, Cannabis,Smoking, Hashish,Smoking, Marihuana,Smoking, Marijuana,Smokings, Blunts
D010552	Personality Assessment	The determination and evaluation of personality attributes by interviews, observations, tests, or scales. Articles concerning personality measurement are considered to be within scope of this term.	Assessment, Personality,Assessments, Personality,Personality Assessments
D011605	Psychoses, Substance-Induced	Psychotic organic mental disorders resulting from the toxic effect of drugs and chemicals or other harmful substance.	Psychoses, Drug,Psychoses, Toxic,Substance-Induced Psychoses,Toxic Psychoses,Drug Psychoses,Psychoses, Substance Induced,Substance Induced Psychoses
D011795	Surveys and Questionnaires	Collections of data obtained from voluntary subjects. The information usually takes the form of answers to questions, or suggestions.	Community Survey,Nonrespondent,Questionnaire,Questionnaires,Respondent,Survey,Survey Method,Survey Methods,Surveys,Baseline Survey,Community Surveys,Methodology, Survey,Nonrespondents,Questionnaire Design,Randomized Response Technique,Repeated Rounds of Survey,Respondents,Survey Methodology,Baseline Surveys,Design, Questionnaire,Designs, Questionnaire,Methods, Survey,Questionnaire Designs,Questionnaires and Surveys,Randomized Response Techniques,Response Technique, Randomized,Response Techniques, Randomized,Survey, Baseline,Survey, Community,Surveys, Baseline,Surveys, Community,Techniques, Randomized Response
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D012307	Risk Factors	An aspect of personal behavior or lifestyle, environmental exposure, inborn or inherited characteristic, which, based on epidemiological evidence, is known to be associated with a health-related condition considered important to prevent.	Health Correlates,Risk Factor Scores,Risk Scores,Social Risk Factors,Population at Risk,Populations at Risk,Correlates, Health,Factor, Risk,Factor, Social Risk,Factors, Social Risk,Risk Factor,Risk Factor Score,Risk Factor, Social,Risk Factors, Social,Risk Score,Score, Risk,Score, Risk Factor,Social Risk Factor
D012569	Schizotypal Personality Disorder	A personality disorder in which there are oddities of thought (magical thinking, paranoid ideation, suspiciousness), perception (illusions, depersonalization), speech (digressive, vague, overelaborate), and behavior (inappropriate affect in social interactions, frequently social isolation) that are not severe enough to characterize schizophrenia.	Incipient Schizophrenia,Latent Schizophrenia,Personality Disorder, Schizotypal,Pseudoneurotic Schizophrenia,Pseudopsychopathic Schizophrenia,Schizophrenia, Borderline,Schizophrenia, Latent,Schizophrenia, Pseudoneurotic,Borderline Schizophrenia,Borderline Schizophrenias,Disorder, Schizotypal Personality,Disorders, Schizotypal Personality,Incipient Schizophrenias,Latent Schizophrenias,Personality Disorders, Schizotypal,Pseudoneurotic Schizophrenias,Pseudopsychopathic Schizophrenias,Schizophrenia, Incipient,Schizophrenia, Pseudopsychopathic,Schizophrenias, Borderline,Schizophrenias, Incipient,Schizophrenias, Latent,Schizophrenias, Pseudoneurotic,Schizophrenias, Pseudopsychopathic,Schizotypal Personality Disorders