Vitamin D for the management of multiple sclerosis.

BACKGROUND: This review is an update of a previously published review, "Vitamin D for the management of multiple sclerosis" (published in the Cochrane Library; 2010, Issue 12). Multiple sclerosis (MS) is characterised by inflammation, demyelination, axonal or neuronal loss, and astrocytic gliosis in the central nervous system (CNS), which can result in varying levels of disability. Some studies have provided evidence showing an association of MS with low levels of vitamin D and benefit derived from its supplementation. OBJECTIVES: To evaluate the benefit and safety of vitamin D supplementation for reducing disease activity in people with MS. SEARCH METHODS: We searched the Cochrane Multiple Sclerosis and Rare Diseases of the CNS Specialized Register up to 2 October 2017 through contact with the Information Specialist with search terms relevant to this review. We included references identified from comprehensive electronic database searches and from handsearches of relevant journals and abstract books from conferences. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs that compared vitamin D versus placebo, routine care, or low doses of vitamin D in patients with MS. Vitamin D was administered as monotherapy or in combination with calcium. Concomitant interventions were allowed if they were used equally in all trial intervention groups. DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data and assessed the methodological quality of studies, while another review author sorted any disagreements. We expressed treatment effects as mean differences (MDs) for continuous outcomes (Expanded Disability Status Scale and number of magnetic resonance imaging (MRI) gadolinium-enhancing T1 lesions), as standardised MDs for health-related quality of life, as rate differences for annualised relapse rates, and as risk differences (RDs) for serious adverse events and minor adverse events, together with 95% confidence intervals (CIs). MAIN RESULTS: We identified 12 RCTs enrolling 933 participants with MS; 464 were randomised to the vitamin D group, and 469 to the comparator group. Eleven trials tested vitamin D3, and one trial tested vitamin D2. Vitamin D3 had no effect on the annualised relapse rate at 52 weeks' follow-up (rate difference -0.05, 95% CI -0.17 to 0.07; I² = 38%; five trials; 417 participants; very low-quality evidence according to the GRADE instrument); on the Expanded Disability Status Scale at 52 weeks' follow-up (MD -0.25, 95% CI -0.61 to 0.10; I² = 35%; five trials; 221 participants; very low-quality evidence according to GRADE); and on MRI gadolinium-enhancing T1 lesions at 52 weeks' follow-up (MD 0.02, 95% CI -0.45 to 0.48; I² = 12%; two trials; 256 participants; very low-quality evidence according to GRADE). Vitamin D3 did not increase the risk of serious adverse effects within a range of 26 to 52 weeks' follow-up (RD 0.01, 95% CI -0.03 to 0.04; I² = 35%; eight trials; 621 participants; low-quality evidence according to GRADE) or minor adverse effects within a range of 26 to 96 weeks' follow-up (RD 0.02, 95% CI -0.02 to 0.06; I² = 20%; eight trials; 701 participants; low-quality evidence according to GRADE). Three studies reported health-related quality of life (HRQOL) using different HRQOL scales. One study reported that vitamin D improved ratings on the psychological and social components of the HRQOL scale but had no effects on the physical components. The other two studies found no effect of vitamin D on HRQOL. Two studies reported fatigue using different scales. One study (158 participants) reported that vitamin D3 reduced fatigue compared with placebo at 26 weeks' follow-up. The other study (71 participants) found no effect on fatigue at 96 weeks' follow-up. Seven studies reported on cytokine levels, four on T-lymphocyte proliferation, and one on matrix metalloproteinase levels, with no consistent pattern of change in these immunological outcomes. The randomised trials included in this review provided no data on time to first treated relapse, number of participants requiring hospitalisation owing to progression of the disease, proportion of participants who remained relapse-free, cognitive function, or psychological symptoms. AUTHORS' CONCLUSIONS: To date, very low-quality evidence suggests no benefit of vitamin D for patient-important outcomes among people with MS. Vitamin D appears to have no effect on recurrence of relapse, worsening of disability measured by the Expanded Disability Status Scale (EDSS), and MRI lesions. Effects on health-related quality of life and fatigue are unclear. Vitamin D3 at the doses and treatment durations used in the included trials appears to be safe, although available data are limited. Seven ongoing studies will likely provide further evidence that can be included in a future update of this review.

Vitamin D for the management of multiple sclerosis.

BACKGROUND: Multiple sclerosis is a disease of the central nervous system characterized by demyelination of the nerve sheaths which can result in varying levels of disability. Disease occurrence and progression are considered by some to be associated with low serum levels of vitamin D. Studies investigating vitamin D supplementation in MS patients have illustrated a noticeable improvement in the course of the disease. OBJECTIVES: To evaluate the safety and effectiveness of vitamin D in the management of multiple sclerosis. SEARCH STRATEGY: We searched the Cochrane Multiple Sclerosis Group Trials Register comprising references identified from comprehensive electronic database searches and hand searches of relevant journals and abstract books of conferences. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials comparing vitamin D with placebo or any other treatment for the management of multiple sclerosis. DATA COLLECTION AND ANALYSIS: Two review authors selected trials for inclusion, assessed the risk of bias and extracted data independently. Disagreements were resolved by consensus. Trialists were contacted for clarification of study details. MAIN RESULTS: We included a single trial (49 participants) conducted over 52 weeks, which treated 25 patients with escalating doses of vitamin D compared with control (24). The trial provided some evidence of the potential benefit of the intervention on several outcomes i.e. the annualised relapse rate; EDSS scores; suppression of T-cell proliferation and illustrated a measure of comparative safety in the relative absence of any adverse events or of high serum calcium levels over the study period. This was a low powered trial with a potential high risk of bias which may ultimately impose limits on the applicability of the available evidence to the MS population as a whole. AUTHORS' CONCLUSIONS: The current level of evidence for the effectiveness of vitamin D supplementation in the management of people with MS is based on a single RCT with potential high risk of bias, which does not at present allow confident decision-making about the use of Vitamin D in MS. Therefore, until further high quality evidence is available, clinicians may wish to consider relevant MS guidelines on vitamin D supplementation when making decisions about the care of people with multiple sclerosis. Adequately powered, multi-centred RCTs with a focus on clinical as well as immunological and MRI outcomes that are meaningful to people with MS, and are able to provide insight into the benefits of Vitamin D in people with MS, are still required.