Hypovitaminosis D association with disease activity in relapsing remitting multiple sclerosis in Brazil

Multiple sclerosis (MS) onset is believed to result from a combination of environmental and genetic factors. A prevailing theory addresses the influence of hypovitaminosis D in the development of MS. This research aimed to study the association between vitamin D serum levels and MS, as a prognostic and risk factor for the development and progression of the disease. A cross-sectional multicenter study was conducted in patients with relapsing-remitting MS (n = 67), according to the revised McDonald criteria (2010), accompanied in three MS centers in different Brazilian states. A control group consisted of healthy volunteers (n = 61). Blood collections were carried out in late summer and late winter. This seems to be the first study of this kind in Latin America. The vitamin D serum levels for MS patients (29.63 ± 8.08) in summer were similar to the controls (29.71 ± 8.28); however, in winter they were lower than the healthy individuals (24.05 ± 7.47 vs 26.56 ± 8.01). No significant difference between the three cities was observed. No association was noted between vitamin D serum levels and gender, race and age, nor correlation of these levels with the EDSS or disease duration. In contrast, a significant association was seen between deficient vitamin D serum levels in late winter with disease activity, characterized by the onset of relapses (19.73 ± 5.69 vs 25.30 ± 6.22) or Gd + lesions (17.22 ± 3.11 vs 22.79 ± 7.22).