The trusted source for
healthcare information and
Does a Lower Vitamin D Level Increase the Risk of Relapse in Inflammatory Spinal Cord Disease?
Abstract & Commentary
By Jai S. Perumal, MD, Assistant Professor of Neurology, Weill Cornell Medical College. Dr. Perumal is a consultant for Biogen Idec and Genzyme, and is on the speakers bureau for Teva and Biogen Idec.
Synopsis: Based on a retrospective analysis of 77 patients with monophasic and recurrent inflammatory spinal cord disease, the authors report significantly lower vitamin D levels in patients with recurrent disease.
Source: Mealy MA, et al. Low serum vitamin D levels and recurrent inflammatory spinal cord disease. Arch Neurol 2012;69:352-356.
The role of vitamin D in autoimmune diseases, including multiple sclerosis (MS), is increasingly recognized. There is growing evidence that lower levels are associated with a higher risk of developing MS and a higher risk of relapses in patients with established MS. Potential molecular mechanisms for the role of vitamin D in immune modulation also have been proposed. Although several studies have shown an inverse relationship between the risk of a relapse and vitamin D level in MS, its role in other central nervous system inflammatory diseases has not been reported. The present study explored the potential relationship between serum vitamin D level and the risk of recurrence in inflammatory spinal cord disease.
This retrospective analysis of 77 patients with inflammatory spinal cord disease included 44 patients with monophasic transverse myelitis and 33 patients with recurrent transverse myelitis. The recurrent group comprised 20 patients with neuromyelitis optica spectrum disorders (NMO), including those with concomitant SLE or Sjogrens disease, and 13 NMO IgG negative patients with recurrent transverse myelitis. The main objective of the study was to investigate a potential association between low serum vitamin D levels and recurrent spinal cord disease. For the analysis, patients were divided into those with monophasic transverse myelitis and recurrent disease. Along with serum 25-hydroxyvitamin D levels, data on patient characteristics (including age, sex, disability level, and the season when vitamin D levels were checked) were collected. In determining the association between vitamin D level and risk of recurrence, the analysis was adjusted for age, race, and sex, since these variables have been independently associated with vitamin D levels in earlier studies.
There were 44 patients in the monophasic transverse myelitis group and 33 patients in the recurrent group. The two groups were similar in several demographic characteristics. When compared with the patients in the monophasic group, patients in the recurrent group had significantly lower vitamin D levels. The mean (SD) 25-hydroxyvitamin D levels were 33 (11.1) ng/mL in the monophasic group and 18 (11.8) ng/mL in the recurrent group. At the Johns Hopkins Hospital laboratory where the analysis was done, vitamin D deficiency is defined as level < 20 ng/mL. After adjusting for demographic characteristics, patients with recurrent disease had a mean (SD) 25-hydorxy vitamin D level that was 10 (3.1) ng/mL lower than patients with monophasic disease.
There is growing evidence for an immune modulatory role of vitamin D in autoimmune disorders including multiple sclerosis. Several studies have investigated environmental risk factors for developing MS and reported an increased risk with lower vitamin D levels. Studies also have looked at the association between serum vitamin D levels and risk of a relapse in patients diagnosed with MS and found an inverse relationship. The present study is the first to explore a potential role for vitamin D in inflammatory spinal cord disease. The authors found significantly lower levels of vitamin D in patients with recurrent spinal cord disease compared to patients with monophasic disease. There are several limitations to this study, including the retrospective nature of the analysis and the variable times from disease onset when vitamin D levels were measured. Even though the analysis was adjusted for known variables that could have influenced vitamin D levels, there could have been other factors that influenced the disease course. Despite the limitations, this study does show significantly lower vitamin D levels in patients with recurrent disease compared to those with monophasic disease. This study warrants further prospective long-term studies, which might help establish an inverse causative association between lower vitamin D levels and the risk for a relapse and if intervention with vitamin D supplementation in those with low vitamin D levels decreases the risk of subsequent relapses in MS and patients with inflammatory spinal cord disease.