OBJECTIVE: The aim of the present study was to explore the pattern of associations between cannabis use and dimensions of psychosis in a nonclinical population of female subjects. METHOD: The Community Assessment of Psychic Experiences (CAPE), a 42-item self-report questionnaire that evolved from the Peters et al. Delusions Inventory [Schizophr. Bull. 25 (1999) 553], was used to measure dimensions of psychosis in a sample of undergraduate female students (n=571). The participants were also asked to complete a self-report questionnaire collecting information on substance use. RESULTS: Three correlated dimensions of positive, negative and depressive experiences were identified using principal components factor analysis. Frequency of cannabis use was independently associated with the intensity of both positive and negative psychotic experiences. No significant association was found between cannabis use and the depressive dimension, or between alcohol use and any of the three positive, negative and depressive dimensions. CONCLUSION: This cross-sectional study supports the hypothesis that exposure to cannabis may induce the emergence of positive psychotic symptoms in subjects without clinical psychosis, and additionally suggests that cannabis users exhibit greater levels of negative symptoms. Prospective studies are required to explore the direction of causality and the impact of cannabis on the course of psychotic experiences in subjects from the general population.
OBJECTIVE: The aim of the present study was to explore the pattern of associations between cannabis use and dimensions of psychosis in a nonclinical population of female subjects. METHOD: The Community Assessment of Psychic Experiences (CAPE), a 42-item self-report questionnaire that evolved from the Peters et al. Delusions Inventory [Schizophr. Bull. 25 (1999) 553], was used to measure dimensions of psychosis in a sample of undergraduate female students (n=571). The participants were also asked to complete a self-report questionnaire collecting information on substance use. RESULTS: Three correlated dimensions of positive, negative and depressive experiences were identified using principal components factor analysis. Frequency of cannabis use was independently associated with the intensity of both positive and negative psychotic experiences. No significant association was found between cannabis use and the depressive dimension, or between alcohol use and any of the three positive, negative and depressive dimensions. CONCLUSION: This cross-sectional study supports the hypothesis that exposure to cannabis may induce the emergence of positive psychotic symptoms in subjects without clinical psychosis, and additionally suggests that cannabis users exhibit greater levels of negative symptoms. Prospective studies are required to explore the direction of causality and the impact of cannabis on the course of psychotic experiences in subjects from the general population.
Authors: Nikie Korver; Piotr J Quee; Heleen B M Boos; Claudia J P Simons; Lieuwe de Haan Journal: Int J Methods Psychiatr Res Date: 2012-03-15 Impact factor: 4.035
Authors: Aine T Behan; Magdalena Hryniewiecka; Colm M P O'Tuathaigh; Anthony Kinsella; Mary Cannon; Maria Karayiorgou; Joseph A Gogos; John L Waddington; David R Cotter Journal: Neuropsychopharmacology Date: 2012-03-21 Impact factor: 7.853
Authors: Cécile Henquet; Lydia Krabbendam; Janneke Spauwen; Charles Kaplan; Roselind Lieb; Hans-Ulrich Wittchen; Jim van Os Journal: BMJ Date: 2004-12-01
Authors: Matti Isohanni; Irene Isohanni; Hannu Koponen; Johanna Koskinen; Pekka Laine; Erika Lauronen; Jouko Miettunen; Pirjo Mäki; Kaisa Riala; Sami Räsänen; Kaisa Saari; Pekka Tienari; Juha Veijola; Graham Murray Journal: Curr Psychiatry Rep Date: 2004-06 Impact factor: 5.285
Authors: Matthew J Smith; Jagadisha Thirthalli; Arbi Ben Abdallah; Robin M Murray; Linda B Cottler Journal: Compr Psychiatry Date: 2008-09-23 Impact factor: 3.735