vitamin b12 deficiency and multiple sclerosis; is there any association?

background: vitamin b12 (cobalamin) deficiency can result in some clinical and paraclinical characteristics similar to what is seen in multiple sclerosis (ms) patients. this study aimed to evaluate the controversial association between vitamin b12 deficiency and ms. methods: we measured serum vitamin b12 in 60 patients with ms and 38 healthy controls. clinical disability was evaluated according to the extended disability status scale (edss). serum b12 concentration was measured with radioimmunoassay dual isotope method. the cutoff value for low serum vitamin b12 concentrations was 75 pg/ml. patients were in remission at the time of blood draw. results: there were 13 (21.6%) ms patients and 10 (26.3%) controls with low serum b12 concentration with no significant difference between the groups; p>0.05. the mean serum vitamin b12 concentration in ms patients (108.9±45.3 pg/ml) was not significantly different compared with controls (98.9±44.4 pg/ml); p=0.284. likewise, there was no correlation between the concentration of serum vitamin b12 and disease’ age of onset, duration, subtypes, or disability status. conclusions: in contrast to some previous reports, our findings did not support any association between b12 deficiency and ms.