is serum vitamin d levels associated with disability in patients with newly diagnosed multiple sclerosis?

background: although the precise etiology of multiple sclerosis (ms) is unknown, it seems that both genetic and environmental factors are important. recent studies suggest that low serum vitamin d levels are important environmental factor in ms. the aim of this study was to compare the serum levels of vitamin d between ms patients and healthy subjects, and to determine its association with disability in ms patients. methods:  in this cross-sectional study, a total of 52 patients with ms were randomly recruited and matched for age and sex with 52 healthy subjects. demographic characteristics and serum vitamin d levels for both groups, as well as duration of disease expanded disability status scale (edss) for ms patients were evaluated. statistical analysis was performed by independent samples t-test and multiple linear regression analysis. results: the mean serum vitamin d levels were 26.5 ± 16.3 ng/ml in ms patients vs. 37.1 ±19.7 in healthy subjects (p = 0.003). a linear regression analysis showed no significant association between vitamin d levels and edss score of patients with ms (p = 0.345), after adjusting for the covariates. conclusion: our findings did not suggest a protective association for serum vitamin d levels against disability in ms patients.