Institute of Medical Sciences (IMS), Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
Am J Addict. 2022 Sep;31(5):454-462. doi: 10.1111/ajad.13305. Epub 2022 Jun 11.
Cannabis is a widely used substance that may impair select cognitive domains, including attention and memory. Problematic cannabis use is a common clinical problem among patients with major depressive disorder (MDD). Few studies have investigated the effects of cannabis abstinence on cognition in MDD. Thus, our study aimed to determine whether a 28-day period of cannabis abstinence is associated with improvements in cognition in patients with MDD and comorbid cannabis use disorder (CUD).
We evaluated the effects of 28 days of cannabis abstinence on cognition in MDD patients with comorbid CUD facilitated by contingency management, motivational interviewing, psychoeducation, and coping-skills training (N = 11). Primary outcomes included Baseline to Day 28 changes in verbal memory and learning, while secondary outcomes included Baseline to Day 28 changes in working memory, visuospatial working memory (VSWM), visual search speed, mental flexibility, response inhibition, attention, manual dexterity, and fine motor movement.
Eight participants (72.7%) met the pre-specified criteria for cannabis abstinence and three participants significantly reduced their cannabis use (≥90%). Visual search speed, selective attention, and VSWM improved over the study period. These improvements were not associated with changes in cannabis metabolite levels from baseline to endpoint.
Our findings suggest that 28 days of cannabis abstinence may improve select cognitive domains in patients with MDD and comorbid CUD.
This is the first study to longitudinally examine the effects of cannabis on cognition in MDD.
Effects of Cannabis Abstinence on Symptoms and Cognition in Depression (NCT03624933; https://www.
gov).
大麻是一种被广泛使用的物质，可能会损害注意力和记忆力等特定认知领域。在患有重度抑郁症（MDD）的患者中，大麻使用障碍是一种常见的临床问题。很少有研究调查大麻戒断对 MDD 患者认知的影响。因此，我们的研究旨在确定在患有 MDD 合并大麻使用障碍（CUD）的患者中，28 天的大麻戒断是否与认知能力的改善相关。
我们通过应急管理、动机访谈、心理教育和应对技能培训来促进 MDD 合并 CUD 患者的 28 天大麻戒断，评估其对认知的影响（N=11）。主要结果包括从基线到第 28 天的言语记忆和学习的变化，次要结果包括从基线到第 28 天的工作记忆、视觉空间工作记忆（VSWM）、视觉搜索速度、心理灵活性、反应抑制、注意力、手的灵巧度和精细运动的变化。
8 名参与者（72.7%）符合大麻戒断的预定标准，3 名参与者显著减少了大麻使用（≥90%）。视觉搜索速度、选择性注意力和 VSWM 在研究期间得到改善。这些改善与从基线到终点的大麻代谢物水平的变化无关。
我们的研究结果表明，28 天的大麻戒断可能会改善 MDD 合并 CUD 患者的特定认知领域。
这是第一项纵向研究大麻对 MDD 患者认知影响的研究。
抑郁症状和认知的大麻戒断影响（NCT03624933；https://www.clinicaltrials.gov）。
