A mixed treatment comparison on efficacy and safety of treatments for spasticity caused by multiple sclerosis: a systematic review and network meta-analysis

Objectives: This study is aimed at providing a quantitative evaluation on different therapies of spasticity caused by multiple sclerosis. Data sources: PubMed and Embase database. Review methods: We searched for randomized controlled trials that met the requirements. Percentages of improved patients' spasticity scale, mild adverse effect and severe adverse effect were extracted as outcomes. The forest plots accompanied with surface under the cumulative ranking curves were used to reveal the efficacy and safety of these therapies. Results: In all, 23 randomized controlled trials with a total of 2720 patients were included in our study. Cannabinoids and botulinum toxin had shown a significantly better efficacy than placebo in the percentage of improved patients. Botulinum toxin also showed such significant difference compared with tizanidine and baclofen. No significant difference was found in spasticity scale. Cannabinoids, tizanidine and diazepam had significantly more mild adverse effect reports than placebo. Surface under the cumulative ranking curves suggested that cannabinoids, botulinum toxin and transcutaneous electric nerve stimulation were preferable therapies. Conclusions: We recommended botulinum toxin as the optimal intervention for multiple sclerosis-related spasticity. Cannabinoids and transcutaneous electric nerve stimulation could also be considered as multiple sclerosis-related spasticity treatments but their safety remained to be verified.