SPP1 and Parkinson disease: Our analysis revealed a model with 16 variables (Aβ40, Aβ42, α-syn, p-Tau, t-Tau, OPN, NFL, IL-6, DJ-1, UCHL1, FLT3LG, MMP2, S100β, ApoA1, ratio of Aβ40/Aβ42 and ratio of p-Tau/t-Tau) able to distinguish early clinical PD from controls with 71% of diagnostic accuracy (AUC-ROC).