Cannabis Dependence, Continuous, Schizophrenia
Conditions
Keywords
Schizophrenia, Cannabis misuse comorbidity, Motivational interview, Randomised open trial
Brief summary
Schizophrenia is a severe mental illness with a lifetime morbidity risk close to 1 %, involving both genetic and environmental risk factors. Prospective studies have shown that heavy use of cannabis in adolescence moderately increases the risk of developing schizophrenia. Many data have also suggested that the co-occurrence of cannabis abuse in patients with schizophrenia has a deleterious impact on the clinical outcome of schizophrenia. Cannabis abuse by schizophrenic patients is a significant public health problem for which there is no empirically validated treatment. We are presently studying the efficiency of motivational therapy on cannabis consumption in patients with schizophrenia.
Detailed description
Schizophrenia is a severe mental illness with a lifetime morbidity risk close to 1 %, involving both genetic and environmental risk factors. Prospective studies have shown that heavy use of cannabis in adolescence moderately increases the risk of developing schizophrenia. Many data have also suggested that the co-occurrence of cannabis abuse in patients with schizophrenia has a deleterious impact on the clinical outcome of schizophrenia. Cannabis abuse by schizophrenic patients is a significant public health problem for which there is no empirically validated treatment. We are presently studying the efficiency of motivational therapy on cannabis consumption in patients with schizophrenia. 330 patients with schizophrenia and cannabis abuse or dependence (according to DSM-IV criteria) are randomly assigned to 4 motivational interview during one month or usual intensive treatment. Treatment is conducted in outpatient which are evaluated at the inclusion and at 6 month with Time-Line Follow Bach for the consumption, PANSS score, number of relapse…). A outcome measure was urinalysis results providing an objective measure of cannabis use throughout the six month of the trial.
Interventions
BEHAVIORALMotivational therapy
One hour of motivational therapy each weak during 4 weeks
BEHAVIORALUsual care
Patients received at least six hour of usual therapy, as in the experimental group
Sponsors
Assistance Publique - Hôpitaux de Paris
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Schizophrenia or schizo-affective disorder according to DSM-IV criteria * Meeting DSM-IV criteria for actual cannabis abuse or dependance * in current and regular contact with mental health service * with an age at interview of 18 years or more * No evidence of organic brain disease or clinically significant concurrent medical illness or learning disability * Written informed consent was obtained from all subjects (patients and parents).
Exclusion criteria
* Not membership to a regime of social security or to a CMU
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Cannabis consumption evaluated by the Time-Line Follow Back at 6 months with mean percentage of abstinent day | inclusion, 3 month, 6 month, 12 month |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| PANSS, GAF, number of DSM-IV criteria of cannabis dependence, May scale for treatment response, SF-12, la URICA, number of hospitalisation, mean number of joints per week, D9THC urinanalysis at 6M and cannabis consumption evaluated by the TLFB at 6M | inclusion, 3 month, 6 month, 12 month. Only inclusion and 6 month for urianalysis | PANSS : global, positive, negative, general scores |
Countries
France
Outcome results
None listed