Plasma NfL concentration was significantly higher in patients with CMT (median 26.0 pg/mL) compared to healthy controls (median 14.6 pg/mL, p < 0.0001) and correlated with disease severity as measured using the Rasch modified CMT examination (r = 0.43, p < 0.0001) and neuropathy (r = 0.37, p = 0.044) scores. Here, NEFL is linked to neuropathy.