In multiple sclerosis patients a single serum neurofilament light chain (sNFL) dosage is strongly associated with 12 months outcome: data from a real-life clinical setting

Background: Neurofilament light chain (NFL) is a neuroaxonal cytoskeletal protein released into cerebrospinal fluid (CSF) and eventually into blood upon neuronal injury. Its detection in serum (sNFL) makes it a promising marker in multiple sclerosis (MS). Objective: To evaluate the usefulness of a single dosage of sNFL in clinical practice. Methods: 626 consecutive relapsing–remitting (RR) MS patients treated with disease modifying treatments (DMTs) for at least 12 months underwent a single sNFL dosage. 553 patients had NEDA-3 status (no relapses, no disability progression, no new/enlarging or contrast-enhancing lesions on brain magnetic resonance imaging) in the 12 months prior blood sampling. sNFL levels were measured by single molecule array (Simoa™). Association between sNFL levels and NEDA-3 status at 12, 24, and 36 months was evaluated with logistic regression models adjusted for sex, EDSS, disease duration, and type of DMTs. Results: 469 out of the 553 NEDA-3 patients had normal...