ABSTRACT
SETTING: Cannabis preparations have been used as a remedy for thousands of years in traditional medicine. Clinical use of cannabinoid substances is restricted, due to legal and ethical reasons, as well as limited evidence showing benefits. OBJECTIVE: To assess the efficacy and harms of cannabis preparations in the treatment of chronic pain. DESIGN: Systematic review and meta-analysis of double-blind randomized controlled trials that compared any cannabis preparation to placebo among subjects with chronic pain. An electronic search was made in Medline/Pubmed, Embase, and The Cochrane Controlled Trials Register (TRIALS CENTRAL) of all literature published until February 2008, as well as specific web pages devoted to cannabis. Studies were cross-checked, selected, and assessed. RESULTS: Eighteen trials were included. The efficacy analysis (visual analog scales) displayed a difference in standardized means in favor of the cannabis arm of -0.61 (-0.84 to -0.37), with statistical homogeneity (I(2) = 0.0%; P = 0.50). For the analysis of harms, the following Odds Ratios (OR) and number needed to harm (NNH) were obtained: for events linked to alterations to perception, OR: 4.51 (3.05-6.66), NNH: 7 (6-9); for events affecting motor function, 3.93 (2.83-5.47), NNH: 5 (4-6); for events that altered cognitive function, 4.46 (2.37-8.37), NNH: 8 (6-12). CONCLUSIONS: Currently available evidence suggests that cannabis treatment is moderately efficacious for treatment of chronic pain, but beneficial effects may be partially (or completely) offset by potentially serious harms. More evidence from larger, well-designed trials is needed to clarify the true balance of benefits to harms.
Subject(s)
Analgesics/administration & dosage , Cannabinoids/administration & dosage , Cannabis/chemistry , Clinical Trials as Topic/statistics & numerical data , Pain, Intractable/drug therapy , Phytotherapy/statistics & numerical data , Analgesics/adverse effects , Cannabinoids/adverse effects , Cannabis/adverse effects , Chronic Disease/drug therapy , Humans , Pain, Intractable/physiopathology , Phytotherapy/adverse effects , Receptors, Cannabinoid/drug effects , Receptors, Cannabinoid/metabolism , Risk Assessment , Treatment OutcomeABSTRACT
OBJECTIVE: The study sought to ascertain the effectiveness of acupuncture as a treatment for fibromyalgia MATERIALS AND METHODS: THE FOLLOWING ELECTRONIC DATABASES WERE SEARCHED: PubMed; The Cochrane Library (CENTRAL); EMBASE; CINAHL; and Pascal Biomed (last date of search: January 2008). We analyzed pain intensity and patient withdrawals prior to termination of the study. A meta-analysis was performed, and a weighted global effect obtained using the inverse of variance. RESULTS: This review covered a total of 6 studies (323 subjects). No statistically significant differences were observed in terms of pain intensity (VAS): 0.02 (-0.24 a 0.28) or withdrawals: RR 0.91 (0.53 a 1.58) CONCLUSION: This systematic review found no evidence of benefit resulting from acupuncture versus placebo, as a treatment for fibromyalgia.