Relation of serum levels of homocysteine, vitamin B12 and folate to cognitive functions in multiple sclerosis patients

Background: Hyperhomocysteinemia, vitamin B12 and folate deficiency have been linked to cognitive dysfunction in multiple sclerosis (MS) patients. Objective: This study aimed to investigate the relation of serum homocysteine (Hcy), vitamin B12 and folate to cognitive functions in MS patients. Subjects and Methods: Forty-five MS patients and twenty matched healthy controls were included. Subjects were submitted to cognitive assessment using a selected psychometric battery and measurement of serum levels of homocysteine, B12 and folic acid. Results: MS patients showed significant worse performance in cognitive scales compared to controls (P  ≤ 0.05). Serum homocysteine, vitamin B12 and folate showed no significant difference between patients and controls (P  > 0.05). Serum homocysteine was negatively correlated with total score of Addenbrooke's Cognitive Examination (ACE), paced auditory serial addition test and controlled oral word association test scores. Serum vitamin B12 was positively correlated with ACE language, visuospatial and total scores and negatively correlated with trail making B score. Serum folate was significantly positively correlated with ACE language and total scores. Homocysteine was the only significant predictor for cognitive impairment in MS patients. Conclusion: Serum homocysteine may play a role in cognitive dysfunction in MS patients.