<b><i>Introduction:</i></b> There is a need for blood biomarkers of disease activity in multiple sclerosis (MS). The aim of the study was to assess the relationship between plasma neurofilament light chain (pNfL) and disease activity as defined by the concept three-domain no evident disease activity (NEDA-3). <b><i>Methods:</i></b> Levels of pNfL (SIMOA) were examined in 159 MS patients and analyzed in relationship to NEDA-3 status (absence of relapse, disability score worsening, and brain magnetic resonance activity) during the last 12 months. The accuracy of the proposed model was evaluated by calculating the area under the receiver operating characteristics (ROC) curve. From the pNfL cutoff, we evaluated the NEDA-NfL status (no relapse, no Expanded Disability Status Scale [EDSS] worsening, and pNfL below the cutoff value). <b><i>Results:</i></b> Levels of pNfL were significantly higher in MS patients than in healthy controls (<i>p</i> < 0.001). From a total of 159 patients, 80 (50.3%) achieved NEDA-3 status, while 79 (49.7%) patients showed evident disease activity (EDA) status. pNfL were significantly lower in the NEDA-3 group than in the EDA group (pNfL mean 7.06 pg/mL [standard deviation (SD) 2.37] vs. pNfL mean 13.04 pg/mL [SD 7.07]) (<i>p</i> < 0.001). ROC analysis showed that pNfL predicts NEDA-3 status (sensitivity and specificity were 80.5 and 72.7%, respectively, <i>p</i> < 0.001), and NEDA-NfL predicts NEDA-3 status (sensitivity and specificity were 97.1 and 82.9%, respectively, <i>p</i> < 0.001). <b><i>Conclusion:</i></b> The results show that pNfL levels are a useful biomarker of disease activity determined by NEDA status in patients with MS and could be an alternative to brain magnetic resonance investigation.
The effect of natalizumab on disability score and relapse rate of multiple sclerosis patients: a prospective cohort study
