Investigating the Neural Correlates of Cognitive Function Associated With Cannabis Abstinence in Psychosis Patients and Non-Psychiatric Controls With Cannabis Use
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 134
- 试验地点
- 2
- 主要终点
- Change in behavior during fMRI task
研究概览
简要总结
Cognitive impairment is well established in people with psychosis and is associated with cannabis use. The current study will investigate the neurobiological basis of cognitive change associated with 28-days of cannabis abstinence in people with psychosis and non-psychiatric controls with cannabis use. Participants will be randomized to a cannabis abstinent group or a non-abstinent control group and will undergo magnetic resonance imaging at baseline and following 28-days of abstinence. This study will help characterize the neuropathophysiological processes underlying cognitive dysfunction associated with cannabis use and its recovery which may guide the development of novel interventions for problematic cannabis use.
详细描述
Background/Importance: Cognitive impairment is well established in people with psychosis and is associated with cannabis use. Despite high rates of cannabis use among people with psychosis and the general population, cannabis' effects on cognition and the brain and their recovery remain unclear. Therefore, this study will investigate the neurobiological basis of changes in cognitive processes associated with cannabis abstinence in people with psychosis and non-psychiatric controls.
Aims: To examine the effects of 28-days of cannabis abstinence in psychosis patients with cannabis use and non-psychiatric controls with cannabis use on (i) brain activity (paired with a memory task); (ii) brain morphology; (iii) to determine if changes in memory following 28-days of abstinence correlate with changes in brain activity and/or morphology and (iv) to determine if baseline brain function and morphology can predict successful abstinence.
Methods: Seventy-four psychosis patients with cannabis use and 60 non-psychiatric controls with cannabis use will be randomized to: (1) contingency reinforcement where biochemically verified abstinence at day 28 will be rewarded; or (2) a non-abstinent control group. The investigators will also recruit a group of healthy non-psychiatric controls (n=40) to determine if neural outcomes in cannabis-using participants do indeed normalize ("recover") following abstinence. Participants will undergo structural and functional magnetic resonance imaging while completing a memory task at baseline (pre-abstinence) and following 28-days of abstinence. Urine samples will be collected twice weekly for abstinence verification.
Relevance: This study will help to characterize the neuropathophysiological processes underlying cognitive dysfunction associated with cannabis use in people with psychosis and non-psychiatric controls which may help to guide the development of novel neurobiologically-informed interventions to treat problematic cannabis use.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Single (Outcomes Assessor)
盲法说明
Research Assistant
入排标准
- 年龄范围
- 16 Years 至 80 Years（Child, Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Able to provide informed consent in English or French
- •Heavy cannabis use (defined as weekly cannabis use for at six months) and/or DSM-5 diagnosis of CUD
- •Have a Full-Scale IQ ≥ 75
- •Meet DSM-5 criteria for a psychotic disorder (psychosis patient arm only)
- •Be an outpatient receiving a stable dose of medication(s) for at least two months (psychosis patient arm only)
- •Clinically stable (as measured by the PANSS-6, total score <30) (psychosis patient arm only)
排除标准
- •current SUD (other than CUD)
- •MRI contraindications
- •Positive urine screen for psychoactive substances other than cannabis, nicotine, or caffeine
- •Current suicidal or homicidal ideation
- •Head injury requiring hospitalization or loss of consciousness > 5 minutes
- •Current medical diseases that requires hospitalization or regular monitoring
- •Being pregnant
- •DSM-5 Axis 1 diagnosis (other than CUD) (non-psychiatric controls only)
- •Taking psychotropic medication
研究组 & 干预措施
Psychosis patients with cannabis use (Abstinent)
Psychosis patients with cannabis use will receive contingency management to encourage cannabis abstinence for 28 days
干预措施: Contingency management (Behavioral)
Psychosis patients with cannabis use (Non-abstinent)
Psychosis Patients with cannabis use who will continue to use cannabis as usual
Non-Psychiatric controls with cannabis use (Abstinent)
Non-Psychiatric controls with cannabis use will receive contingency management to encourage cannabis abstinence for 28 days
干预措施: Contingency management (Behavioral)
Non-Psychiatric controls with cannabis use (Non-abstinent)
Non-Psychiatric Controls with cannabis use will continue to use cannabis as usual
Non-Psychiatric Controls without cannabis use
Non-Psychiatric controls without cannabis use
结局指标
主要结局
Change in behavior during fMRI task
时间窗: Baseline, Day 28
Behavioral responses (episodic memory performance) will be recorded by an external button box. These responses will be used to assess encoding accuracy during an episodic memory task.
Change in fMRI brain activity pattern
时间窗: Baseline, Day 28
fMRI will be used to measure differences between baseline (day 0) and day 28 in hemodynamic (BOLD) responses while participants complete a memory task
次要结局
- Change in brain morphology: gray matter volume(Baseline, Day 28)
- Change in brain morphology: diffusion(Baseline, Day 28)
- Change in brain morphology: cortical thickness(Baseline, Day 28)
研究者
Rachel Rabin
Assistant Professor
Douglas Mental Health University Institute