In the PD group, neither p-tau181 nor NfL concentrations at baseline were associated with the Non-motor Symptoms Scale (NMSS) Attention/Memory Domain score (Domain 5) (rho = −0.073, p = 0.500 for p-tau181, and rho = −0.083, p = 0.445 for NfL) (Supplementary Fig. 1a, d). Here, NEFL is linked to Parkinson disease.