Department of Psychiatry, Dalhousie University, AJLB, 5909 Veterans' Memorial Lane, Halifax, NS B3H 2E2, Canada; Nova Scotia Health, AJLB, Room 4066, 5909 Veterans' Memorial Lane, Halifax, NS B3H 2E2, Canada.
Department of Psychology & Neuroscience, Dalhousie University, 1355 Oxford St., Halifax, NS B3H 4R2, Canada.
Mult Scler Relat Disord. 2022 Jan;57:103338. doi: 10.1016/j.msard.2021.103338. Epub 2021 Oct 18.
Multiple sclerosis (MS) is a chronic demyelinating disease which leads to sensory, motor, autonomic, and cognitive symptoms. Cannabis is a common way for persons with MS (pwMS) to seek symptomatic therapy. Given the capacity for both cannabis and MS to cause cognitive impairment, it is important to determine whether there is any negative impact when the two co-occur. The objective of this systematic review was to evaluate the effects of cannabis and medicinal cannabinoid products on cognition in pwMS in order to provide guidance to clinicians and enable them to make evidence-based recommendations regarding cannabis and cannabinoid products.
A systematic review was carried out searching common keyword combinations for cannabis and MS across five databases, producing 840 unique articles, 18 of which were included in a qualitative synthesis.
Aggregate data from existing studies to date highlight potential impairments from chronic whole-plant cannabis use in commonly affected cognitive domains in multiple sclerosis, including attention and working memory, and to a lesser extent, visual memory, verbal memory, and executive function. Results also suggest that in the short-term, medicinal cannabinoid preparations do not significantly impair cognition and may even ameliorate cognitive symptoms in the context of obtrusive MS disease. The findings are limited by disparities in detail of cannabis use data reported across whole-plant cannabis publications.
Existing literature on co-occurrence of cannabis use and MS lacks high quality evidence to recommend for or against cannabis and cannabinoid therapies for pwMS based on cognitive effects. Existing data suggest that cognition may be differentially impacted in pwMS depending on the type of product, the duration of use, and the indication. Future studies on whole-plant cannabis require comprehensive cannabis use data reporting including frequency, dosing, duration, and type of cannabis product. Future studies on medicinal cannabinoid products should be long-term to assess the effects of chronicity.
多发性硬化症（MS）是一种慢性脱髓鞘疾病，可导致感觉、运动、自主和认知症状。大麻是 MS 患者（pwMS）寻求对症治疗的常见方法。鉴于大麻和 MS 都有导致认知障碍的能力，因此确定两者同时存在时是否会产生任何负面影响非常重要。本系统评价的目的是评估大麻和药用大麻素产品对 pwMS 认知的影响，以便为临床医生提供指导，并使他们能够就大麻和大麻素产品提出基于证据的建议。
通过在五个数据库中搜索大麻和 MS 的常见关键字组合，进行了系统评价，产生了 840 篇独特的文章，其中 18 篇被纳入定性综合分析。
现有研究的综合数据突出了慢性全植物大麻使用对多发性硬化症中常见受影响认知领域的潜在损害，包括注意力和工作记忆，在较小程度上还包括视觉记忆、言语记忆和执行功能。结果还表明，在短期内，药用大麻素制剂不会显著损害认知能力，甚至可能在多发性硬化症疾病的干扰下改善认知症状。这些发现受到全植物大麻出版物中报告的大麻使用数据细节差异的限制。
关于大麻使用和 MS 共存的现有文献缺乏高质量的证据，无法根据认知影响来推荐 pwMS 使用大麻和大麻素治疗。现有数据表明，认知可能会根据产品类型、使用时间和适应证的不同而受到不同的影响。未来关于全植物大麻的研究需要全面报告大麻使用数据，包括频率、剂量、持续时间和大麻产品类型。未来关于药用大麻素产品的研究应该是长期的，以评估慢性的影响。
