Corticosteroids for the long-term treatment in multiple sclerosis.

Background: Short term high dose corticosteroid treatment improves symptoms and short term disability after an acute exacerbation of multiple sclerosis (MS) but it is unknown whether its long-term use can reduce the accumulation of disability.
Objectives: To determine the efficacy and safety of long-term corticosteroid use in MS.
Search Strategy: We searched the following bibliographic databases: CENTRAL (Issue 1, 2007), MEDLINE (1966 to February 2007) and EMBASE (1980 to February 2007). In an effort to identify further published, unpublished and ongoing trials we searched reference lists and contacted trial authors and one pharmaceutical company.
Selection Criteria: We considered controlled, randomised trials (RCTs), with or without blinding, of long term treatment (i.e. longer than 6 months) of any type of corticosteroid in MS, irrespective of disease course.
Data Collection and Analysis: Reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information.
Main Results: Three trials, all classified at high risk of bias, contributed to this review (Miller 1961; BPSM 1995; Zivadinov 2001) resulting in a total of 183 participants (91 treated). Corticosteroid therapy did not reduce the risk of being worse at the end of follow-up (odds ratio [OR] 0.51, 95% confidence interval [CI] 0.26 to 1.02) but there was a substantial heterogeneity between studies (I(2): 78.4%). I. v. periodic high dose methylprednisolone (MP) was associated with a significant reduction in the risk of disability progression at 5 years in relapsing-remitting (RR) MS (OR 0.26, 95% CI 0.10 to 0.66), while oral continuous low dose prednisolone was not associated with any risk reduction in disability progression at 18 months (OR 1.23, 95% CI 0.43 to 3.56). Risk of experiencing at least one exacerbation at end of follow-up was not significantly reduced with corticosteroid treatment (OR 0.36; 95% CI 0.10 to 1.25). Only one study recorded adverse events: in one patient i. v. MP was discontinued after the fourth pulse when he developed acute glomerulonephritis; a second patient was removed from the study after the fifth i. v. MP pulse because of severe osteoporosis.
Authors' Conclusions: There is no enough evidence that long-term corticosteroid treatment delays progression of long term disability in patients with MS. Since one study at high risk of bias showed that the administration of pulsed high dose i. v. MP is associated with a significant reduction in the risk of long term disability progression in patients with RR MS, an adequately powered, high quality RCT is needed to investigate this finding.