An international team led by Harvard researchers, funded by the National Multiple Sclerosis Society and the National Institutes of Health, has found that levels of vitamin D in serum early in the course of MS may be predictive of later disease activity and progression. Those with higher levels tended to have reduced disease activity and progression, and those with lower levels tended to experience more disease activity and progression. This study, which leveraged data from an industry-funded clinical trial, adds to growing evidence of links between vitamin D and MS. Identifying such lifestyle factors that can benefit everyone affected by MS is a priority area of focus for the National MS Society. Alberto Ascherio, MD, DrPH (Harvard School of Public Health, Boston) and colleagues report their findings in JAMA Neurology (published online January 20, 2014).
Background: A number of genetic and environmental factors influence whether a person will get MS. Research is increasingly pointing to a reduced level of vitamin D in the blood as a risk factor for developing MS. Vitamin D is produced by the body when the skin is exposed to sunshine, and it can also be found in some foods. In lab mice, vitamin D supplementation can reduce the effects of an MS-like disease. In people with MS, high vitamin D levels have been associated with decreased risk for attacks and less severe disability. Clinical trials, including one supported by the National MS Society, are underway to test whether vitamin D supplements, added to standard therapy, can provide benefits to people who have MS.
Although there are differences of opinion as to how much vitamin D is optimal, a deficiency is often defined as a serum level of less than 50 nmol per liter of 25-hydroxyvitamin D.
The Study: This group sought to determine whether vitamin D levels observed early in the course of MS would predict later disease activity and progression. The study leveraged data accumulated from a completed clinical trial originally sponsored by Bayer called the BENEFIT study, which was designed to determine whether interferon beta-1b could delay the onset of clinically definite MS in people with a clinically isolating syndrome (a single neurologic episode indicating high risk for MS).
Dr. Ascherio’s team evaluated vitamin D levels among BENEFIT participants. A total of 465 participants had at least one vitamin D measurement taken, and 334 patients had vitamin D levels taken at both six and 12 months after starting the study. There were two groups of BENEFIT participants – one group received interferon immediately and the other group received it later. All participants were followed for 5 years. Dr. Ascherio’s team looked for links between vitamin D levels and MS relapses, progression of disability (using the standard EDSS scale), and disease activity and tissue integrity observed on MRI scans.
They compared outcomes for participants whose serum vitamin D levels were 50 nmol/l or higher with those whose serum levels were lower than 50 nmol/l within the first 12 months of the study. Among their findings, they reported that those with higher levels of vitamin D, regardless of whether they were taking interferon or not, were less likely to progress to the diagnosis of definite MS, had a significantly lower amount of new disease activity on MRI, brain tissue volume loss, and disease progression on the EDSS.
Conclusions: These findings add to the growing evidence that vitamin D may help to reduce the effects of MS. Results from current controlled clinical trials now underway in people with MS should help determine and define the impact of taking vitamin D.
Dr. Ascherio and colleagues comment on the work that is left to do. “Further investigations are needed to determine the optimal levels of vitamin D and whether results apply to different races or ethnicities, to patients with the secondary or primary progressive course of MS, or in combination with drugs other than IFNB-1b.”
Read more about ongoing research on vitamin D and MS.
Read about (link to mom2011summer.pdf) recommendations for vitamin D supplements and people with MS.