NEFL and myeloid sarcoma: Among MS patients, correlations between NfL (or GFAP) levels and EDSS scores were comparable between the age groups (Pearson r, <47 years vs. ≥47 years, NfL: 0.403 vs. 0.275, p = 0.457; GFAP: 0.193 vs. 0.360, P = 0.355).