Multiple Sclerosis: Relationships Between Cytokines, MRI Lesion Burden, Visual Evoked Potentials and Disability Scores

Aim: The aim of this study was to investigate the relationships between the disability (EDSS) scores, magnetic resonance imaging (MRI) lesion burden, the visual evoked potential (VEP) latencies and the cytokine levels in patients with multiple sclerosis (MS) that previously not studied.
Method: Study group consisted of 40 MS patients with either relapsing-remitting (RR) (n=29) or secondary progressive course (n=11) and control group comprised 35 matched healthy subjects. Student’s t test, Mann-Whitney U, Chi-squared and correlation analyses were used for statistical analyses.
Result: In patient group EDSS scores varied from 1.5 to 8.5, all had abnormal MRI T2 plaque burden and 65.0% had abnormal VEP latencies. Serum levels of tumor necrosis factor-alpha (TNF-а) and interleukin-2 receptor (IL-2R) were significantly higher in patients compared to controls (P<0.001 and P<0.001, respectively). Serum levels of IL-6 and IL-10 were similar in patients and controls (P> 0.05). The total EDSS scores significantly correlated with the T2 plaque counts (r=0.637, P<0.001). Among all measured cytokines, only IL-8 levels were significantly correlated with the total EDSS scores and MRI lesion burden (r=0.590, P<0.001 and r=0.535, P<0.001, respectively). Other cytokine levels did not correlate with the disability scores, the amount of MRI lesions or the VEP latencies (P> 0.05).
Conclusion: Our data indicate that despite clinical stability, immunological activity is not interrrupted in MS and the production of different cytokines were not uniformly affected by the immunomodulator medication. New therapeutic strategies correcting cytokine balance may be useful in MS.

Keywords
Multiple sclerosis, cytokines, disability, MRI, visual evoked potentials