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Effects of Cannabis Abstinence on Symptoms and Cognition in Depression

Not Applicable
Completed
Conditions
Cannabis Use Disorder
Major Depressive Disorder
Cognition
Interventions
Behavioral: Weekly Behavioral Coaching Session
Behavioral: Contingency Management
Registration Number
NCT03624933
Lead Sponsor
Centre for Addiction and Mental Health
Brief Summary

The objective of this study is to assess the changes in symptoms and cognition that occur after a 28-day abstinence period in patients with comorbid Cannabis Use Disorder (CUD) and Major Depression (MDD). This study employs a 28-day abstinence paradigm a total of 8 visits to the CAMH Russell site (screening, training, baseline, week 1, week 2, week 3, week 4, follow-up). Participants should be between the ages of 18-55, meet criteria for moderate depression and CUD, be non-treatment seeking, and be on a stable dose of antidepressant medication. The study visits will take up a total of approximately 22.5 hours with compensation for time provided. These visits will involve multiple clinical, substance use, and cognitive assessments. Abstinence will be maintained by weekly behavioural coaching sessions and contingency reinforcement.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
19
Inclusion Criteria
  • ages 18-55
  • meet DSM-5 diagnostic criteria for cannabis use disorder (cannabis use >1 g/day, CUDIT score >12)
  • meet DSM-5 diagnostic criteria for Major Depressive Disorder as determined using the SCID
  • be an outpatient receiving a stable dose of antidepressant medication(s) for at least 1 month
  • have a Hamilton Depression Rating Scale (HDRS-17) baseline total score greater than 14
  • have a Full Scale IQ greater than 80 as determined by the WTAR
  • be a non-treatment seeking cannabis user
  • evidence of sufficient motivation and effort as measure by a Test of Memory Malingering (TOMM) score greater than 45
  • urinary baseline THC-COOH levels greater than 150 ng/ml
Exclusion Criteria
  • meets criteria for abuse or dependence of alcohol or other illicit substances within the part 6 months (with the exception of cannabis, nicotine, or caffeine)
  • positive urine screen for illicit substances other than cannabis, nicotine or caffeine
  • current suicidal or homicidal ideation
  • psychotic disorder diagnosis (e.g. schizoaffective disorder, major depression with psychotic features) as determined by the SCID
  • head injury with loss of consciousness greater than 2 minutes or requiring hospitalization
  • neurological or medical condition determined to effect cognition
  • be treatment seeking for cannabis use

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
28-Day Cannabis AbstinenceWeekly Behavioral Coaching SessionThe study will assess the changes that occur after a 28-day abstinence period in patients with Major Depressive Disorder (MDD) and comorbid Cannabis Use Disorder (CUD). Patients will be instructed to initiate abstinence 12 hours prior to the baseline session and will come in for weekly visits involving a series of clinical, cognitive, and substance use assessments.
28-Day Cannabis AbstinenceContingency ManagementThe study will assess the changes that occur after a 28-day abstinence period in patients with Major Depressive Disorder (MDD) and comorbid Cannabis Use Disorder (CUD). Patients will be instructed to initiate abstinence 12 hours prior to the baseline session and will come in for weekly visits involving a series of clinical, cognitive, and substance use assessments.
Primary Outcome Measures
NameTimeMethod
The effects of 28 day cannabis abstinence on change in depressive symptoms in cannabis-dependent patients with Major Depressive Disorder (MDD) as assessed by the Hamilton Rating Scale for Depression (HRSD).Weekly (Day 0, Day 7, Day 14, Day 21, Day 28) and at 8 weeks (Follow-up Day 56)

The clinical assessment will be administered weekly during the abstinence period and conducted by study personnel. The HRDS is used to evaluate depression on a 17-item scale with higher values indicating worse depressive symptoms.

Secondary Outcome Measures
NameTimeMethod
The effects of 28 day cannabis abstinence on change in co-occurring anxiety in cannabis dependent patients with MDD as assessed by the Beck Anxiety Inventory (BAI) administered weekly.Weekly (Day 0, Day 7, Day 14, Day 21, Day 28) and at 8 weeks (Follow-up Day 56)

The clinical assessment will be administered at Baseline, weekly during the abstinence period and Follow-up and will be conducted by study personnel. The BAI is a 21-item scale used to evaluate the severity of anxiety symptoms with higher values indicating worse outcomes.

The effects of 28 day cannabis abstinence on change in cognitive function in cannabis dependent patients with Major Depressive Disorder (MDD) as assessed by a cognitive battery administered at Baseline, Week 2, Endpoint and Follow-Up.Bi-Weekly (Day 0, Day 14, Day 28) and at 8 Weeks (Follow-up Day 56)

The cognitive battery will include the primary outcome of verbal memory (assessed by Hopkins Verbal Learning Test) and will be compared to baseline (Day 1) performance. Cortical inhibition will also be assessed and compared.

Trial Locations

Locations (1)

Centre for Addiction and Mental Health

🇨🇦

Toronto, Ontario, Canada

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