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TC2A COMT VAL 158MET MODERATION OF CANNABIS INUDCED PSYCHOSIS: AN EXPERIENCE SAMPLING STUDY (ESM)
Symposium 12: Cannabis and psychosis: from genetics and biology to functional outcome and treatment Information Campaigns, and the second (NoIC, N = 75) between January 1, 2002 and June 30, 2004 with no Information Campaigns. Both samples were offered an equivalent assessment and treatment program for first-episode psychosis. Both samples had access to early Detection Teams. Results: The DUP was significantly longer for patients in the NoIC cohort (Medians: 15 weeks vs 5 weeks). Clinical status at baseline was worse for the the NoIC cohort (and will be detailed). Conclusion: Intensive education about psychosis and its early signs appears to be necessary for reducing DUP.
Symposium 12: Cannabis and psychosis: from genetics and biology to functional outcome and treatment Chairs: C.E.C. Henquet & C.M. Corcoran TC2A COMT VAL158 MET MODERATION OF CANNABIS INUDCED PSYCHOSIS: AN EXPERIENCE SAMPLING STUDY (ESM) C.E.C. Henquet1 *, A. Rosa2 , J van Os1 , I. Myin-Germeys1 . 1 Maastricht University, Maastricht, Netherlands, 2 University of Barcelona, Barcelona, Spain Presenting author contact: [email protected] Introduction: A functional polymorphism in the Catechol-OMethyltransferase (COMT Val158 Met) gene may moderate the psychosis-inducing effects of cannabis. In order to extent this finding to dynamic effects in the flow of daily life, a momentary assessment study of psychotic symptoms in response to cannabis use was conducted. Patterns of use in daily life in relation to psychotic symptoms and positive and negative affect, were furthermore examined to investigate possible selfmedication effects. Methods: The ESM time-sampling technique was used to collect data on cannabis use and occurrence of symptoms in daily life in patients with a psychotic disorder, relatives of patients with a psychotic disorder and healthy controls (N = 61). Results: Subjects with the Val/Val genotype, but not those with one or more Met alleles, showed an increase in hallucinations after cannabis exposure, conditional on prior evidence of psychometric psychosis liability. In the patient group, positive affect, but not negative affect nor psychotic symptoms, predicted use of cannabis. Discussion: The findings confirm that in people with psychometric evidence of psychosis liability, COMT Val158 Met genotype moderates the effects of cannabis on psychotic phenomena in the flow of daily life. There was no evidence that selfmedication effects could explain use of cannabis in daily life in individuals with a psychotic disorder.
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TC2B TEMPORAL ASSOCIATION OF CANNABIS USE AND PERCEPTUAL DISTURBANCES IN PRODROMAL PATIENTS C.M. Corcoran *, D. Kimhy, A. Stanford, Y. Sanchez, R.A. Seckinger, D. Printz, J. MacDonald, F. Levin, J. Lieberman, D. Malaspina. New York State Psychiatric Institute/Columbia, New York NY, United States Presenting author contact: [email protected] Introduction: Psychotic disorders and cannabis abuse are highly comorbid; both have their antecedents in adolescence, a critical period characterized by profound brain and behavioural changes. Yet the co-evolution of cannabis misuse and psychotic disorders is poorly understood. The prospective study of high-risk prodromal patients can shed light on how cannabis use and psychotic symptoms develop over time. Methods: We evaluated 26 prodromal patients (85% men; ages 14−25 (mean 19.2; SD 3.7); 42% white). They were evaluated at baseline and every 3 months for up to 2 years for prodromal (SIPS/SOPS positive, negative) and mood (Hamilton depression, anxiety) symptoms, function (GAF), cannabis and other drug use (# days), life events (# negative), and medication status. Patients had baseline diagnostic interviews for substance abuse diagnoses (DIGS; K-SADS). Results: 12 patients endorsed any drug use history. All had used cannabis; half had dependence. A quarter abused alcohol and half tried hallucinogens and/or cocaine. Users were older, with more positive and fewer negative symptoms. Prospectively, there was no incident drug use: users and nonusers remained discrete. Other drug use was rare. Conversion to psychosis was 18% at 1 year. Cannabis was temporally associated with perceptual disturbances (p = 0.010), anxiety (p = 0.008), and poor function (p = 0.034), controlling for life events and medications. In multivariate analysis, only the relationships of cannabis use to perceptual disturbances (p = 0.007) and poor function (p = 0.02) were significant.
Cannabis use and positive symptoms in one patient. Discussion: Prodromal patients have a diathesis that confers vulnerability to affective and psychotic-like symptoms in the context of cannabis use; this can inform treatment strategies.
Symposium 12: Cannabis and psychosis: from genetics and biology to functional outcome and treatment Chairs: C.E.C. Henquet & C.M. Corcoran TC2A COMT VAL158 MET MODERATION OF CANNABIS INUDCED PSYCHOSIS: AN EXPERIENCE SAMPLING STUDY (ESM) C.E.C. Henquet1 *, A. Rosa2 , J van Os1 , I. Myin-Germeys1 . 1 Maastricht University, Maastricht, Netherlands, 2 University of Barcelona, Barcelona, Spain Presenting author contact: [email protected] Introduction: A functional polymorphism in the Catechol-OMethyltransferase (COMT Val158 Met) gene may moderate the psychosis-inducing effects of cannabis. In order to extent this finding to dynamic effects in the flow of daily life, a momentary assessment study of psychotic symptoms in response to cannabis use was conducted. Patterns of use in daily life in relation to psychotic symptoms and positive and negative affect, were furthermore examined to investigate possible selfmedication effects. Methods: The ESM time-sampling technique was used to collect data on cannabis use and occurrence of symptoms in daily life in patients with a psychotic disorder, relatives of patients with a psychotic disorder and healthy controls (N = 61). Results: Subjects with the Val/Val genotype, but not those with one or more Met alleles, showed an increase in hallucinations after cannabis exposure, conditional on prior evidence of psychometric psychosis liability. In the patient group, positive affect, but not negative affect nor psychotic symptoms, predicted use of cannabis. Discussion: The findings confirm that in people with psychometric evidence of psychosis liability, COMT Val158 Met genotype moderates the effects of cannabis on psychotic phenomena in the flow of daily life. There was no evidence that selfmedication effects could explain use of cannabis in daily life in individuals with a psychotic disorder.
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TC2B TEMPORAL ASSOCIATION OF CANNABIS USE AND PERCEPTUAL DISTURBANCES IN PRODROMAL PATIENTS C.M. Corcoran *, D. Kimhy, A. Stanford, Y. Sanchez, R.A. Seckinger, D. Printz, J. MacDonald, F. Levin, J. Lieberman, D. Malaspina. New York State Psychiatric Institute/Columbia, New York NY, United States Presenting author contact: [email protected] Introduction: Psychotic disorders and cannabis abuse are highly comorbid; both have their antecedents in adolescence, a critical period characterized by profound brain and behavioural changes. Yet the co-evolution of cannabis misuse and psychotic disorders is poorly understood. The prospective study of high-risk prodromal patients can shed light on how cannabis use and psychotic symptoms develop over time. Methods: We evaluated 26 prodromal patients (85% men; ages 14−25 (mean 19.2; SD 3.7); 42% white). They were evaluated at baseline and every 3 months for up to 2 years for prodromal (SIPS/SOPS positive, negative) and mood (Hamilton depression, anxiety) symptoms, function (GAF), cannabis and other drug use (# days), life events (# negative), and medication status. Patients had baseline diagnostic interviews for substance abuse diagnoses (DIGS; K-SADS). Results: 12 patients endorsed any drug use history. All had used cannabis; half had dependence. A quarter abused alcohol and half tried hallucinogens and/or cocaine. Users were older, with more positive and fewer negative symptoms. Prospectively, there was no incident drug use: users and nonusers remained discrete. Other drug use was rare. Conversion to psychosis was 18% at 1 year. Cannabis was temporally associated with perceptual disturbances (p = 0.010), anxiety (p = 0.008), and poor function (p = 0.034), controlling for life events and medications. In multivariate analysis, only the relationships of cannabis use to perceptual disturbances (p = 0.007) and poor function (p = 0.02) were significant.
Cannabis use and positive symptoms in one patient. Discussion: Prodromal patients have a diathesis that confers vulnerability to affective and psychotic-like symptoms in the context of cannabis use; this can inform treatment strategies.