Eadie Lauren, Lo Lindsay A, Christiansen April, Brubacher Jeffrey R, Barr Alasdair M, Panenka William J, MacCallum Caroline A
Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada.
Department of Psychology, Queens University, Kingston, ON, Canada.
Front Psychiatry. 2021 Mar 12;12:638962. doi: 10.3389/fpsyt.2021.638962. eCollection 2021.
While the recreational use of cannabis has well-established dose-dependent effects on neurocognitive and psychomotor functioning, there is little consensus on the degree and duration of impairment typically seen with medical marijuana use. Compared to recreational cannabis users, medical cannabis patients have distinct characteristics that may modify the presence and extent of impairment. The goal of this review was to determine the duration of acute neurocognitive impairment associated with medical cannabis use, and to identify differences between medical cannabis patients and recreational users. These findings are used to gain insight on how medical professionals can best advise medical cannabis patients with regards to automobile driving or safety-sensitive tasks at work. A systematic electronic search for English language randomized controlled trials (RCTs), clinical trials and systematic reviews (in order to capture any potentially missed RCTs) between 2000 and 2019 was conducted through Ovid MEDLINE and EMBASE electronic databases using MeSH terms. Articles were limited to medical cannabis patients using cannabis for chronic non-cancer pain or spasticity. After screening titles and abstracts, 37 relevant studies were subjected to full-text review. Overall, seven controlled trials met the inclusion/exclusion criteria and were included in the qualitative synthesis: six RCTs and one observational clinical trial. Neurocognitive testing varied significantly between all studies, including the specific tests administered and the timing of assessments post-cannabis consumption. In general, cognitive performance declined mostly in a THC dose-dependent manner, with steady resolution of impairment in the hours following THC administration. Doses of THC were lower than those typically reported in recreational cannabis studies. In all the studies, there was no difference between any of the THC groups and placebo on any neurocognitive measure after 4 h of recovery. Variability in the dose-dependent relationship raises the consideration that there are other important factors contributing to the duration of neurocognitive impairment besides the dose of THC ingested. These modifiable and non-modifiable factors are individually discussed.
虽然大麻的娱乐性使用对神经认知和心理运动功能具有明确的剂量依赖性影响，但对于医用大麻使用时通常出现的损害程度和持续时间，人们几乎没有达成共识。与娱乐性大麻使用者相比，医用大麻患者具有不同的特征，这些特征可能会改变损害的存在和程度。本综述的目的是确定与医用大麻使用相关的急性神经认知损害的持续时间，并确定医用大麻患者与娱乐性使用者之间的差异。这些研究结果有助于深入了解医疗专业人员如何就汽车驾驶或工作中的安全敏感任务，为医用大麻患者提供最佳建议。通过Ovid MEDLINE和EMBASE电子数据库，使用医学主题词（MeSH）对2000年至2019年间的英文随机对照试验（RCT）、临床试验和系统评价（以捕捉任何可能遗漏的RCT）进行了系统的电子检索。文章仅限于将大麻用于慢性非癌性疼痛或痉挛的医用大麻患者。在筛选标题和摘要后，对37项相关研究进行了全文审查。总体而言，七项对照试验符合纳入/排除标准，并纳入了定性综合分析：六项RCT和一项观察性临床试验。所有研究之间的神经认知测试差异很大，包括所采用的具体测试以及大麻消费后评估的时间。一般来说，认知表现大多以四氢大麻酚（THC）剂量依赖性方式下降，在THC给药后的数小时内损害逐渐缓解。THC的剂量低于娱乐性大麻研究中通常报道的剂量。在所有研究中，恢复4小时后，任何THC组与安慰剂组在任何神经认知指标上均无差异。剂量依赖性关系的变异性引发了这样的思考，即除了摄入的THC剂量外，还有其他重要因素影响神经认知损害的持续时间。这些可改变和不可改变的因素将分别进行讨论。
