Treatments for spasticity and pain in multiple sclerosis: a systematic review

Abstract

OBJECTIVES: To identify the drug treatments currently available for the management of spasticity and pain in multiple sclerosis (MS), and to evaluate their clinical and cost-effectiveness. DATA SOURCES: Electronic bibliographic databases, National Research Register, MRC Clinical Trials Register and the US National Institutes of Health Clinical Trials Register. REVIEW METHODS: Systematic searches identified 15 interventions for the treatment of spasticity and 15 interventions for treatment of pain. The quality and outcomes of the studies were evaluated. Reviews of the treatment of spasticity and pain when due to other aetiologies were also sought. RESULTS: There is limited evidence of the effectiveness of four oral drugs for spasticity: baclofen, dantrolene, diazepam and tizanidine. Tizanidine appears to be no more effective than comparator drugs such as baclofen and has a slightly different side-effects profile. Despite claims that it causes less muscle weakness, there was very little evidence that tizanidine performed any better in this respect than other drugs, although it is more expensive. The findings of this review are consistent with reviews of the same treatments for spasticity derived from other aetiologies. There is good evidence that both botulinum toxin (BT) and intrathecal baclofen are effective in reducing spasticity, and both are associated with functional benefit. However, they are invasive, and substantially more expensive. None of the studies included in the review of pain were designed specifically to evaluate the alleviation of pain in patients with MS and there was no consistency regarding the use of validated outcome measures. It was suggested that, although expensive, the use of intrathecal baclofen may be associated with significant savings in hospitalisation costs in relation to bed-bound patients who are at risk of developing pressure sores, thus enhancing its cost-effectiveness. No studies of cost-effectiveness were identified in the review of pain. There is evidence, albeit limited, of the clinical effectiveness of baclofen, dantrolene, diazepam, tizanidine, intrathecal baclofen and BT and of the potential cost-effectiveness of intrathecal baclofen in the treatment of spasticity in MS. CONCLUSIONS: Many of the interventions identified are not licensed for the alleviation of pain or spasticity in MS and the lack of evidence relating to their effectiveness may also limit their widespread use. Indeed, forthcoming information relating to the use of cannabinoids in MS may result in there being better evidence of the effectiveness of new treatments than of any of the currently used drugs. It may therefore be of value to carry out double-blind randomised controlled trials of interventions used in current practice, where outcomes could include functional benefit and impact on quality of life. Further research into the development and validation of outcomes measures for pain and spasticity may also be useful, as perhaps would cost-utility studies.