APOA1 and Parkinson disease: In PD group CSF ApoAI LMW and lipoprotein-bound aSN were correlating with patients age at onset (Fig. 2, p = 0.05, r = 0.18 and p = 0.02, r = 0.22 respectively) and, on the other hand, CSF ApoAI HMW negatively correlated with age at onset (p = 0.05, r = − 0.18).