Amongst prion disease groups, NfL was higher in sCJD than in both symptomatic IPD (z = 7.8, p < 0.0001) and vCJD (z = 3.28, p = 0.014), but no other pairwise comparisons showed significant differences (all p > 0.05). Here, NEFL is linked to variant Creutzfeldt-Jakob disease.