Cannabinoids for treating neurogenic lower urinary tract dysfunction in patients with multiple sclerosis: a systematic review and meta-analysis.

OBJECTIVES: To review systematically all the available evidence on efficacy and safety of cannabinoids for treating neurogenic lower urinary tract dysfunction (NLUTD) in patients with multiple sclerosis (MS). PATIENTS AND METHODS: The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies were identified by electronic search of the Cochrane register, Embase, Medline, Scopus (last search on 11 November 2016). RESULTS: After screening 8 469 articles, we included two randomized controlled trials and one open-label study, in which a total of 426 patients were enrolled. Cannabinoids relevantly decreased the number of incontinence episodes in all three studies. Pooling data showed the mean difference in incontinence episodes per 24 h to be -0.35 (95% confidence interval -0.46 to -0.24). Mild adverse events were frequent (38-100%), but only two patients (0.7%) reported a serious adverse event. CONCLUSIONS: Preliminary data imply that cannabinoids might be an effective and safe treatment option for NLUTD in patients with MS; however, the evidence base is poor and more high-quality, well-designed and adequately powered and sampled studies are urgently needed to reach definitive conclusions.