R Kuepper1, J van Os, R Lieb, H-U Wittchen, C Henquet. 1. Department of Psychiatry and Neuropsychology, South Limburg Mental Health Research and Teaching Network, EURON, Maastricht University Medical Center, Maastricht, The Netherlands.
Abstract
BACKGROUND: Cannabis use is considered a component cause of psychotic illness, interacting with genetic and other environmental risk factors. Little is known, however, about these putative interactions. The present study investigated whether an urban environment plays a role in moderating the effects of adolescent cannabis use on psychosis risk. METHOD: Prospective data (n=1923, aged 14-24 years at baseline) from the longitudinal population-based German Early Developmental Stages of Psychopathology cohort study were analysed. Urbanicity was assessed at baseline and defined as living in the city of Munich (1562 persons per km2; 4061 individuals per square mile) or in the rural surroundings (213 persons per km2; 553 individuals per square mile). Cannabis use and psychotic symptoms were assessed three times over a 10-year follow-up period using the Munich version of the Composite International Diagnostic Interview. RESULTS: Analyses revealed a significant interaction between cannabis and urbanicity [10.9% adjusted difference in risk, 95% confidence interval (CI) 3.2-18.6, p=0.005]. The effect of cannabis use on follow-up incident psychotic symptoms was much stronger in individuals who grew up in an urban environment (adjusted risk difference 6.8%, 95% CI 1.0-12.5, p=0.021) compared with individuals from rural surroundings (adjusted risk difference -4.1%, 95% CI -9.8 to 1.6, p=0.159). The statistical interaction was compatible with substantial underlying biological synergism. CONCLUSIONS: Exposure to environmental influences associated with urban upbringing may increase vulnerability to the psychotomimetic effects of cannabis use later in life.
BACKGROUND: Cannabis use is considered a component cause of psychotic illness, interacting with genetic and other environmental risk factors. Little is known, however, about these putative interactions. The present study investigated whether an urban environment plays a role in moderating the effects of adolescent cannabis use on psychosis risk. METHOD: Prospective data (n=1923, aged 14-24 years at baseline) from the longitudinal population-based German Early Developmental Stages of Psychopathology cohort study were analysed. Urbanicity was assessed at baseline and defined as living in the city of Munich (1562 persons per km2; 4061 individuals per square mile) or in the rural surroundings (213 persons per km2; 553 individuals per square mile). Cannabis use and psychotic symptoms were assessed three times over a 10-year follow-up period using the Munich version of the Composite International Diagnostic Interview. RESULTS: Analyses revealed a significant interaction between cannabis and urbanicity [10.9% adjusted difference in risk, 95% confidence interval (CI) 3.2-18.6, p=0.005]. The effect of cannabis use on follow-up incident psychotic symptoms was much stronger in individuals who grew up in an urban environment (adjusted risk difference 6.8%, 95% CI 1.0-12.5, p=0.021) compared with individuals from rural surroundings (adjusted risk difference -4.1%, 95% CI -9.8 to 1.6, p=0.159). The statistical interaction was compatible with substantial underlying biological synergism. CONCLUSIONS: Exposure to environmental influences associated with urban upbringing may increase vulnerability to the psychotomimetic effects of cannabis use later in life.
Authors: Brandon Abbs; Rashmin M Achalia; Adegoke O Adelufosi; Ahmet Yiğit Aktener; Natalie J Beveridge; Savita G Bhakta; Rachael K Blackman; Emre Bora; M S Byun; Maurice Cabanis; Ricardo Carrion; Christina A Castellani; Tze Jen Chow; M Dmitrzak-Weglarz; Charlotte Gayer-Anderson; Felipe V Gomes; Kristen Haut; Hiroaki Hori; Joshua T Kantrowitz; Taishiro Kishimoto; Frankie H F Lee; Ashleigh Lin; Lena Palaniyappan; Meina Quan; Maria D Rubio; Sonia Ruiz de Azúa; Saddichha Sahoo; Gregory P Strauss; Aleksandra Szczepankiewicz; Andrew D Thompson; Antonella Trotta; Laura M Tully; Hiroyuki Uchida; Eva Velthorst; Jared W Young; Anne O'Shea; Lynn E Delisi Journal: Schizophr Res Date: 2012-08-19 Impact factor: 4.939
Authors: Karin J H Verweij; Abdel Abdellaoui; Michel G Nivard; Alberto Sainz Cort; Lannie Ligthart; Harmen H M Draisma; Camelia C Minică; Gonneke Willemsen; Jouke-Jan Hottenga; Jacqueline M Vink Journal: Drug Alcohol Depend Date: 2017-01-10 Impact factor: 4.492