Meng Howard, Johnston Bradley, Englesakis Marina, Moulin Dwight E, Bhatia Anuj
From the *Department of Anesthesia and Pain Management, University Health Network-Toronto Western Hospital, University of Toronto, Toronto, Ontario, Canada; †Department of Anaesthesia and Pain Medicine and ‡Child Health Evaluative Sciences, The Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada; §Institute of Health Policy, Management and Evaluation, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; ‖Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Ontario, Canada; ¶Library and Information Services, Toronto General Hospital, University Health Network, Toronto, Ontario, Canada; and #Department of Clinical Neuro Sciences and Oncology Earl Russell Chair Pain Research, Western University, London Regional Cancer Program, London, Ontario, Canada.
Anesth Analg. 2017 Nov;125(5):1638-1652. doi: 10.1213/ANE.0000000000002110.
There is a lack of consensus on the role of selective cannabinoids for the treatment of neuropathic pain (NP). Guidelines from national and international pain societies have provided contradictory recommendations. The primary objective of this systematic review and meta-analysis (SR-MA) was to determine the analgesic efficacy and safety of selective cannabinoids compared to conventional management or placebo for chronic NP.
We reviewed randomized controlled trials that compared selective cannabinoids (dronabinol, nabilone, nabiximols) with conventional treatments (eg, pharmacotherapy, physical therapy, or a combination of these) or placebo in patients with chronic NP because patients with NP may be on any of these therapies or none if all standard treatments have failed to provide analgesia and or if these treatments have been associated with adverse effects. MEDLINE, EMBASE, and other major databases up to March 11, 2016, were searched. Data on scores of numerical rating scale for NP and its subtypes, central and peripheral, were meta-analyzed. The certainty of evidence was classified using the Grade of Recommendations Assessment, Development, and Evaluation approach.
Eleven randomized controlled trials including 1219 patients (614 in selective cannabinoid and 605 in comparator groups) were included in this SR-MA. There was variability in the studies in quality of reporting, etiology of NP, type and dose of selective cannabinoids. Patients who received selective cannabinoids reported a significant, but clinically small, reduction in mean numerical rating scale pain scores (0-10 scale) compared with comparator groups (-0.65 points; 95% confidence interval, -1.06 to -0.23 points; P = .002, I = 60%; Grade of Recommendations Assessment, Development, and Evaluation: weak recommendation and moderate-quality evidence). Use of selective cannabinoids was also associated with improvements in quality of life and sleep with no major adverse effects.
Selective cannabinoids provide a small analgesic benefit in patients with chronic NP. There was a high degree of heterogeneity among publications included in this SR-MA. Well-designed, large, randomized studies are required to better evaluate specific dosage, duration of intervention, and the effect of this intervention on physical and psychologic function.
对于选择性大麻素在治疗神经性疼痛（NP）中的作用，目前尚无共识。国家和国际疼痛协会的指南给出了相互矛盾的建议。本系统评价和荟萃分析（SR-MA）的主要目的是确定与传统治疗或安慰剂相比，选择性大麻素治疗慢性NP的镇痛效果和安全性。
我们检索了将选择性大麻素（屈大麻酚、纳布啡、纳比西莫尔）与传统治疗（如药物治疗、物理治疗或两者结合）或安慰剂用于慢性NP患者的随机对照试验，因为NP患者可能正在接受上述任何一种治疗，或者如果所有标准治疗均未能提供镇痛效果和/或这些治疗伴有不良反应，则可能未接受任何治疗。检索了截至2016年3月11日的MEDLINE、EMBASE和其他主要数据库。对NP及其亚型（中枢性和外周性）的数字评分量表得分数据进行荟萃分析。使用推荐分级评估、制定和评价方法对证据的确定性进行分类。
本SR-MA纳入了11项随机对照试验，共1219例患者（选择性大麻素组614例，对照组合605例）。研究在报告质量、NP病因、选择性大麻素的类型和剂量方面存在差异。与对照组相比，接受选择性大麻素治疗的患者平均数字评分量表疼痛评分（0-10分制）有显著但临床上较小的降低（-0.65分；95%置信区间，-1.06至-0.23分；P = 0.002，I² = 60%；推荐分级评估、制定和评价：弱推荐，中等质量证据）。使用选择性大麻素还与生活质量和睡眠改善相关，且无重大不良反应。
选择性大麻素对慢性NP患者有较小的镇痛益处。本SR-MA纳入的出版物之间存在高度异质性。需要设计良好的大型随机研究，以更好地评估具体剂量、干预持续时间以及该干预对身体和心理功能的影响。
