Abstract
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 methods
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.
Plain language summary
Vitamin D for the management of multiple sclerosis
Multiple sclerosis is an illness in which the myelin sheaths around the nerves of the brain and spinal cord are damaged, affecting the ability of nerve cells to communicate with each other. A wide range of clinical presentations and neurological symptoms can occur with the disease, and these can progress to physical and cognitive disability often with a variable clinical course. Although very little is known about the mechanism and causes of this disease genetic, immunologic and environmental factors have all been implicated. Studies have shown a characteristic geographical pattern of disease distribution both in occurrence and progression, which appear to be correlated with sun light exposure and lack of vitamin D and are considered to be predisposing factors for MS. Vitamin D deficiency is said to affect the general well being of patients with MS and is also associated with poorer neurologic outcomes. People suffering with MS are usually given regular vitamin D preparations after assessment of their serum levels of vitamin D.This review sought to evaluate the benefits and harms of this Vitamin D administration to people of MS.The current level of evidence from this review is based on only one trial with potential high risk of bias, which does not at present allow confident decision-making about the use of Vitamin D in MS. The review authors suggest that until further high-level evidence is available, clinicians should continue to follow local guidelines when administering vitamin D to people with MS.However, the question of the safety and effectiveness of Vitamin D in people of MS remains unanswered.
Further research, consisting of well-designed and adequately-powered randomised controlled trials, should aim to provide reliable evidence for people to make informed decisions as to whether this treatment can be effective in the management of MS