Genetic Counselling in the Prevention of Mental Health Consequences of Cannabis Use (IMAGINE)

February 6, 2023 updated by: Rudolf Uher, Nova Scotia Health Authority

Interdisciplinary Approach to Maximize Adolescent Potential: Genetic Counselling Interventions to Reduce Negative Environmental Effects

Severe mental illness (SMI) refers to the most burdensome psychiatric conditions. The need to pre-empt the onset of SMI is pressing because once SMI develops, quality of life is poor and available treatments have limited efficacy. Most risk factors for SMI are either unchangeable (e.g., genetics) or difficult to alter (e.g., low socio-economic status). In contrast, cannabis use is one specific risk factor that could be avoided. Certain individuals are more vulnerable to the harmful effects of cannabis. Genetic factors can help us identify these high-risk individuals. One in three individuals are carriers of a higher-risk genetic variant, and cannabis users with this genotype are at up to 7-fold increased risk of developing schizophrenia. In our study, genetic counselling will be provided to participants by a board-certified genetic counsellor. During the genetic counselling session, participants will have the option to receive their genotype. Participants will be counselled regarding their individualized risk of developing and of not developing SMI based on family history, whether or not they choose to use cannabis, and genotype (if the participants accept the genetic test results). The investigators hypothesize that this intervention will reduce exposure to cannabis compared to the youth who are not offered the intervention.

Study Overview

Detailed Description

Severe mental illness (SMI) refers to the most burdensome forms of psychiatric disorder, including schizophrenia, bipolar disorder, and severe depression. These illnesses typically emerge in adolescence or young adulthood and are associated with substantial impairment in functioning. A significant proportion (~30%) of individuals with SMI remain resistant to any form of available pharmacotherapy. The combination of early onset, poor response to treatment and persistent disability makes SMI the most problematic group of illnesses to individuals and society. The need for early interventions to pre-empt the onset of SMI is pressing because once SMI develops, quality of life is poor for patients and their families. There is substantial overlap in the genetic and environmental risk factors for individual forms of SMI, and predictors of SMI are not specific to any one disorder. It is therefore necessary to conceptualize SMI as transdiagnostic and include diagnoses of schizophrenia, bipolar disorder, and depression, rather than focusing on single illnesses when developing preventative interventions. Prevention of SMI is currently hindered by the inability to identify those at risk early enough to normalize their developmental trajectory. Recent advances in genomics and the understanding of important gene-environment interactions may help overcome this challenge and enable effective and targeted prevention of SMI. Cannabis exposure during critical periods of brain maturation is an avoidable environmental risk factor for SMI. A replicated gene-cannabis interaction shows that carriers of a common genetic variant (C alleles at rs2494732 in the AKT1 gene) are at up to 7-fold increased risk of developing psychosis if they use cannabis. Genetic counselling provides a powerful tool to communicate genetic information to youth in a way that empowers and enhances health. The present project involves the delivery of a genetic counselling intervention to inform youth of their personalized risk of developing SMI based on genotype, family history, and whether or not they choose to use cannabis. This project will be the first application of molecular genetic information and genetic counselling to prevent SMI.

Aim: To test if genetic counselling regarding personalized risk information based on a replicated gene-cannabis interaction reduces cannabis use in youth at high risk of developing severe mental illness.

Hypotheses:

  1. A genetic counselling intervention will be acceptable to youth at high familial risk of SMI.
  2. A genetic counselling intervention with personalized feedback of AKT1 genotype will reduce cannabis use among vulnerable youth.
  3. The effect of the intervention will be moderated by AKT1 genotype, with greater reduction of cannabis use among carriers of the sensitive C alleles.

Method: A cohort of over 450 youth (aged 3-29) has been enrolled as part of the Families Overcoming Risks and Building Opportunities for Well-being (FORBOW) study. The investigators have obtained biological samples for measurement of genetic variation and the investigators will obtain biological samples to measure cannabis exposure. The investigators will randomly select one in every two eligible youth (aged 12-21) to be offered genetic counselling during which the participants will be provided with personalized genetic information and they will be counselled regarding risk of developing SMI based on genotype, family history, and whether or not they choose to use cannabis. The investigators will follow the participants through the developmental period with the highest risk of cannabis use initiation and the investigators will assess cannabis use and psychopathology annually. The primary outcome will be abstinence from cannabis reported by participants in confidential interviews and confirmed by measurement of the primary metabolites of psychoactive Δ9-tetrahydrocannabinol in blood and urine samples.

Significance: This project will realize the first translational application of a gene-environment interaction to improve mental health and test an intervention with potential public health benefits.

Study Type

Interventional

Enrollment (Anticipated)

120

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Nova Scotia
      • Halifax, Nova Scotia, Canada, B3H 2E2
        • Recruiting
        • Nova Scotia Health Authority

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

12 years to 21 years (ADULT, CHILD)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Enrolment in the Families Overcoming Risks and Building Opportunities for Well-being (FORBOW) study.
  • Age between 12 and 21 years.
  • Knowledge of English sufficient to benefit from the intervention.
  • Capacity to provide informed consent at most recent FORBOW assessment.
  • Provision of consent to be contacted about future studies at most recent FORBOW assessment.

Exclusion Criteria:

  • A diagnosis of severe mental illness (psychotic disorder, bipolar disorder, severe/recurrent depression) at baseline
  • Autism or intellectual disability of a degree that interferes with assessment (IQ < 70)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: PREVENTION
  • Allocation: RANDOMIZED
  • Interventional Model: PARALLEL
  • Masking: SINGLE

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
EXPERIMENTAL: Genetic counselling
Eligible participants who are randomized will be contacted and offered an invitation to attend the intervention. Genetic counselling will be provided to participants who accept the intervention as a single 1-2 hour session by a board-certified genetic counsellor. During the genetic counselling session, participants will have the option to receive their genotype at rs2494732. Participants will be counselled regarding their individualized risk of developing and of NOT developing SMI based on family history, whether or not they choose to use cannabis, and genotype (if they accept the genetic test results). Approximately 1 month after the intervention, participants will receive a follow-up interview.
Participants will receive information on risk/protective factors and causes of mental illness. Participants are not required to receive numeric/genetic risk information. Participants who choose to receive genetic and/or numeric risk information will be counselled on their risk of NOT developing and of developing SMI based on their genetic test results and/or family history information they provide. Risk estimates will be derived by genetic counsellors, according to standard practice guidelines. Participants who receive genetic information will be counselled on the possible influence of cannabis use on risk of mental illness based on their genotype. Participants who choose to not receive genetic information will be counselled on the influence of cannabis on mental health.
NO_INTERVENTION: Control group
Eligible participants who are not randomized to be offered the intervention will continue with their annual assessments as part of the parent study. These participants will receive the current standard of care (no intervention), and will not be offered or informed of the intervention.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Self-reported cannabis use
Time Frame: 1 month
Self-reported cannabis use on a questionnaire.
1 month

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
The proportion of participants who complete the intervention after receiving an offer to participate (intervention acceptability)
Time Frame: Completion of study (2 years).
Acceptability will be established as the proportion of individuals accepting the offer of intervention.
Completion of study (2 years).
Presence of cannabinoids in urine
Time Frame: 1 month
Urine will be screened for the presence/absence of cannabinoids.
1 month

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (ACTUAL)

November 1, 2019

Primary Completion (ANTICIPATED)

September 1, 2024

Study Completion (ANTICIPATED)

September 1, 2024

Study Registration Dates

First Submitted

July 5, 2018

First Submitted That Met QC Criteria

July 17, 2018

First Posted (ACTUAL)

July 26, 2018

Study Record Updates

Last Update Posted (ACTUAL)

February 8, 2023

Last Update Submitted That Met QC Criteria

February 6, 2023

Last Verified

February 1, 2023

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Schizophrenia

Clinical Trials on Genetic counselling

3
Subscribe