Abstract
Introduction: Serum neurofilament light chain (sNfL) has become a promising biomarker for acute and chronic neuroaxonal damage in relapsing and progressive multiple sclerosis (MS). Evidence is accumulating that sNfL levels have a predictive value for the risk of disability progression in MS. Objectives/Aims: To assess serum neurofilament light chain (sNfL) levels in patients with progressive MS. Methods: We analysed sNfL levels in a cross-sectional cohort study involving 181 patients with progressive MS (PMS). Additionally, we investigated the correlation between disease activity and sNfL levels in 341 patients with relapsing MS (RMS) using single molecule array technology. Results: Serum NfL levels (pg/mL) were significantly elevated in patients with RMS and PMS compared to HC (29.4 vs 12.3, p<0.05; 38.4 vs 12.3, p<0.001, respectively). Additionally, higher sNfL levels were correlated with disability. A statistically significant difference in sNfL levels was observed between relapsing and progressive disease in individuals not receiving treatment (35.2 vs 42.0, p<0.01, adjusted for age). Furthermore, treatment significantly reduced sNfL levels in RMS compared to those not receiving treatment (24.4 vs 36.9, p<0.01, adjusted for age). Notably, a statistically significant difference was observed only with natalizumab and fingolimod, but not with interferons or glatiramer acetate when compared to individuals not receiving treatment. Conclusion: The findings support the utility of sNfL measurement to monitor MS disease activity and progression alongside magnetic resonance imaging.