Document Type : Special Articles


1 Department of Neurology, Neuroscience Research Center, Imam Reza Hospital, Tabriz University of Medical Sciences, Tabriz, Iran.

2 Department of Neurology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.

3 Department of Nutrition, School of Nutrition and Health, Tabriz University of Medical Sciences, Tabriz, Iran.


Background: It seems that serum vitamin D levels are one of the potential environmental factors affecting the severity of multiple sclerosis (MS). In this study, we aim to evaluate vitamin D levels in MS patients and healthy subjects and assess the relationship between vitamin D level and disability.Methods: In this case-control study, 168 rapid relapsing MS patients and 168 matched healthy controls were randomly included in this study. Demographic characteristics and serum vitamin D levels for patients and controls, as well as expanded disability status scale (EDSS), duration of disease and diagnostic lag for patients were evaluated. We followed up patients for 6 months and relapses were recorded.Results:  The  mean  serum  vitamin  D  levels  were 19.16 ± 17.37 inpatients and 25.39 ± 19.67 in controls (P = 0.560). The mean serum vitamin D levels were 12.65 ±  13.3 in patients with relapses and 22.08 ± 18.22 in  patients without any relapses (P < 0.001). There  was  no  significant  correlation  between  E SS score and serum vitamin D levels (r = −0.08, P = 0.280). There  was  a  significant  positive  correlation  between EDSS score and disease duration (r = 0.52, P < 0.001).Conclusion: In conclusion, vitamin D level in patients with  MS  was  significantly  lower  than  the  healthy subjects,  but  no  significant  relationship  was  found between vitamin D levels and disability.  Our findings did not suggest a protective role for serum vitamin D levels against disability.