Relation of Serum Uric Acid Level with Cognitive Functions and Number of Plaques in Patients with Relapsing-Remitting Multiple Sclerosis

Objective: Several studies have identified impaired performance on the cognition test in people with multiple sclerosis (MS), yet uncertainty remains over the cause of this impairment. The aim of this study was to evaluate the correlation of serum uric acid (UA) level with cognitive impairment and magnetic resonance imaging (MRI) lesions in patients with relapsing-remitting multiple sclerosis (RRMS).Methods: In this study, 50 adults patients with RRMS (disease period 1-5 years) were assessed with neuropsychological test batteries and laboratory blood studies. All the patients were subjected to oranial MRI examination and clinical evaluation with the expanded disability status scale (EDSS) was applied. Results: Cognitive impairment was found in 44% of the patients. Mean UA serum level was measured as 4.38±1.60 mg/dl (2-9 mg/dl) and the mean EDSS score was 2.09±2.01 (0-7). Even it is not statistically significant, the relation between serum UA level and cognitive functions or number of plaques on MRI was found at about statistically significant level (p=0.09). A statistically significant correlation was observed between the scores of the concentration and distractibility subtest scores of the ADAS-cog test and the serum UA levels (p=0.01). However, the effects of exhaustion and emotional disorders on this relation can not be excluded.Conclusion: Our findings suggest that in RRMS patients there is no primary deficit in serum uric acid. Cognitive impairment and total MRI lesion load in RRMS patients are not directly effected by serum UA level. (Archives of Neuropsychiatry 2010; 47: 333-7)