Baseline serum neurofilament light chain: a diagnostic biomarker in drug-naïve multiple sclerosis patients

Abstract Background Multiple sclerosis (MS) is a chronic autoimmune disease characterized by neurodegeneration and demyelination. This study evaluated the diagnostic value of baseline serum neurofilament light chain (sNFL) levels and their correlation with clinical variables in treatment-naive MS patients. In this cross-sectional study, we assessed 134 treatment-naive MS patients and 37 healthy controls. Clinical evaluations included the Expanded Disability Status Scale (EDSS), 9-Hole Peg Test (9-HPT), 25-Foot Walk Test (25-FWT), Hamilton depression and anxiety scales, and sNFL levels measured using ELSA. Results sNFL levels were significantly higher in MS patients (45.50 pg/ml) than in controls (9.20 pg/ml) with remarkable diagnostic performance. ROC curve analysis revealed an area under the curve of 0.965, a cut-off value of 15.52 pg/ml, 96.3% sensitivity, and 89.2% specificity. SPMS patients exhibited the highest sNFL levels, with significant correlations observed between sNFL and physical disability measures, including EDSS ( p = 0.389, p < .001), 9-Hole Peg Test (9-HPT) ( p = 0.386, p < .001; moderate positive), and 25-Foot Walk Test (25-FWT) ( p = 0.354, p < .001). Conclusion This study suggests sNFL as a promising biomarker for MS diagnosis, capable of differentiating disease phenotypes and assessing disability in drug-naive patients. The significant correlations between sNFL levels and clinical measures indicate potential for predicting disease progression risk. Trial registration: The study protocol was registered retrospectively at ClinicalTrials.gov ID NCT06197841. https://clinicaltrials.gov/study/NCT06197841?cond=NCT06197841&rank=1 .