Early Clinical Predictors of Long-term Disability Progression in Patients with Multiple Sclerosis

Background: One of the unmet therapeutic needs in the treatment of multiple sclerosis (MS) is to prevent the accumulation of irreversible disability. Formulating standardized predictors of conversion in the secondary progressive phase of the relapsing-remitting MS (RRMS) should be a step toward solving this problem. Objective: To develop a reliable score, a predictor of physical disability worsening and secondary progression in patients with RRMS. Materials and Methods: Seventy-four patients with RRMS were observed retrospectively for 15 years. Clinical and demographic parameters were analyzed with respect to the time of reaching Expanded Disability Status Scale (EDSS) 4 and/or EDSS 6, as well as EDSS at the end of 15 years. Results: Almost half of the patients observed (47%) reached irreversible disability (EDSS ≥4.0) and ¼ developed secondary progression (EDSS 6.0). The statistically significant variables selected were age at onset of MS, sex, type (afferent, efferent, and combined), and number of symptoms during the first and second attacks. Based on this selection, a predictive score for the course of the disease was formed. It has a sensitivity of 86%, specificity of 89%, positive predictive value of 85%, and negative predictive value of 81%. Conclusion: The proposed predictive score can be applied as a complementary tool in the choice of appropriate therapeutic approach at the early stages of MS, which can help avoid disability overtime.