Assessment of the Relationship Between Red Cell Distribution Width and Multiple Sclerosis

Accumulating data have shown that immune and inflammatory factors are involved in the pathogenesis of multiple sclerosis (MS), and loss of polyunsaturated fatty acids from plasma and blood cell membranes has also been reported in patients with MS, contributing to the variation of erythrocyte deformability. Therefore, the aim of this investigation was to assess the association between red blood cell distribution width (RDW) and MS. A total of 109 patients with MS and 130 healthy individuals were enrolled into the study, and MS patients receiving treatment of subcutaneous recombinant Rebif (IFN-β1a) were followed retrospectively. Complete blood cell counts and Expanded Disability Status Scale (EDSS) score were evaluated in patients with MS before and after treatment. RDW values were significantly higher in patients with MS compared with the controls (13.6 ± 0.89 vs 12.8 ± 0.38, P < 0.001); a positive correlation between RDW and EDSS score was observed in patients with MS (r = 0.789, P < 0.001). Significant differences in the value of RDW and EDSS score were observed between treatment-naive patients and treated patients (13.6 ± 0.95 vs 12.7 ± 0.44, P < 0.001; 3.6 ± 1.39 vs 1.5 ± 0.60, P < 0.001). RDW was associated independently with MS in logistic regression analysis (odds ratio = 7.007; 95% confidence interval [CI] 3.461-14.187; P < 0.001), and receiver-operating characteristics (ROC) analysis showed that a RDW measurement >13.11% evaluated MS with a sensitivity of 70.0% and a specificity of 84.7%, and the area under the ROC curve for RDW was calculated as 0.80 (95% CI 0.739-0.859, P < 0.001). The level of RDW was decreased in treatment responders with the reduction of EDSS score; a strong relationship was also observed in treatment responders between RDW and EDSS score (r = 0.733, P < 0.001), and covariance analysis indicated RDW values decreased significantly in treatment responders (P = 0.025). Our results suggest that elevated RDW values are associated with EDSS score in patients with MS, and the relationship is remarkably influenced by Rebif treatment; RDW may be a useful marker to estimate disability status and treatment effectiveness in patients with MS.