Plain language summary
Epidemiological research shows that Vitamin D status is associated with reduced activity and progression of disease in multiple sclerosis (MS). This review assessed the evidence from ten double-blind randomised controlled trials, including a total of 627 adults with relapsing remitting MS (RRMS), for the clinical effectiveness of vitamin D supplementation compared to placebo in disease and symptom management. The results from the reviewed studies on disease progression and immunological blood parameters were mixed. Where benefits of vitamin D supplementation were seen this tended to be in those groups where vitamin D levels were low at the start of the study. Those studies evaluating the safety and tolerability of vitamin D reported no serious adverse events. The authors conclude that baseline serum vitamin D levels may be a predictor of improvements in RRMS with vitamin D supplementation, and that further research should include baseline vitamin D as part of the assessment.
OBJECTIVE to examine the extent of effect vitamin D in Multiple Sclerosis (MS) on pathology and symptoms. METHODS A literature search was performed in November 2018 (CRD42018103615). Eligibility criteria: randomised control trials in English from 2012 to 2018; a clinical diagnosis of MS; interventions containing vitamin D supplementation (vitamin D3 or calcitriol) in disease activity compared to a control/placebo; improvement in: serum 25(OH)D, relapse rates, disability status by Expanded Disability Status Scale (EDSS) scores, cytokine profile, quality of life, mobility, T2 lesion load and new T2 or T1 Gd enhancing lesions, safety and adverse effects. Risk of bias was evaluated. RESULTS Ten studies were selected. The study size ranged from 40 to 94 people. All studies evaluated the use of vitamin D supplementation (ranging from 10 to 98,000 IU), comparing to a placebo or low dose vitamin D. The duration of the intervention ranged from 12 to 96 weeks. One trial found a significant effect on EDSS score, three demonstrated a significant change in serum cytokines level, one found benefits to current enhancing lesions and three studies evaluating the safety and tolerability of vitamin D reported no serious adverse events. Disease measures improved to a greater extent overall in those with lower baseline serum 25(OH)D levels. CONCLUSIONS As shown in 3 out of 10 studies, improvement in disease measures may be more apparent in those with lower baseline vitamin D levels.