Clinical trial NCT03624933: Effects of Cannabis Abstinence on Symptoms and Cognition in Depression
Official title: Effects of Extended Cannabis Abstinence on Symptoms and Cognition in Depressed Individuals
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Cannabis Use Disorder
Major Depressive Disorder
Cognition
Keywords: Depression
Cognitive Functioning
Cannabis Use Disorder
Lead sponsor: Centre for Addiction and Mental Health
Sponsor class: OTHER
First posted: 2018-08-10
Enrollment: 19
Sex: ALL
Minimum age (years): 18
Maximum age (years): 55
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Intervention model description: This is an open label intervention of contingent reinforcement and behavioral support to try to enhance cannabis abstinence for 28 days with people with Major Depressive Disorder. We will analyze data post hoc from this study as a function of subjects who attain abstinence versus those who do not.
Primary purpose: TREATMENT

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.


Eligibility criteria: 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

Primary outcomes:
measure: 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).
timeFrame: Weekly (Day 0, Day 7, Day 14, Day 21, Day 28) and at 8 weeks (Follow-up Day 56)
Secondary outcomes:
measure: 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.
timeFrame: Bi-Weekly (Day 0, Day 14, Day 28) and at 8 Weeks (Follow-up Day 56)
measure: 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.
timeFrame: Weekly (Day 0, Day 7, Day 14, Day 21, Day 28) and at 8 weeks (Follow-up Day 56)
Other outcomes:
Locations:
city: Toronto
country: Canada
facility: Centre for Addiction and Mental Health
state: Ontario
Study officials:
affiliation: Centre for Addiction and Mental Health
name: Tony George, M.D., FRCPC
role: PRINCIPAL_INVESTIGATOR
References:
citation: Sorkhou M, Rabin RA, Rabin JS, Kloiber S, McIntyre RS, George TP. Effects of 28 days of cannabis abstinence on cognition in major depressive disorder: A pilot study. Am J Addict. 2022 Sep;31(5):454-462. doi: 10.1111/ajad.13305. Epub 2022 Jun 11.