Plasma NfL, GFAP, amyloid, and p-tau species as Prognostic biomarkers in Parkinson’s disease

IntroductionThe prognostic role of plasma neurofilament light chain (NfL), phospho-tau, beta-amyloid, and GFAP is still debated in Parkinson's disease (PD).MethodsPlasma p-tau181, p-tau231, A beta 1-40, A beta 1-42, GFAP, and NfL were measured by SIMOA in 136 PD with 2.9 + 1.7 years of follow-up and 76 controls. Differences in plasma levels between controls and PD and their correlation with clinical severity and progression rates were evaluated using linear regression analyses.ResultsPatients exhibited similar distribution of plasma biomarkers but higher P-tau181, P-tau231 and lower A beta 1-42 compared with controls. NfL and GFAP correlated with baseline motor and non-motor severity measures. At follow-up, NfL emerged as the best predictor of progression with marginal effect of GFAP and p-tau181 adjusting for age, sex, disease duration, and baseline motor severity.ConclusionThe present findings confirmed plasma NfL as best predictor of progression in PD, with a marginal role of p-tau181 and GFAP.