Considering that some of the DLB markers correlate with α-syn load, we next analyzed whether these markers were also dysregulated in PD using the publicly available CSF PEA-proteomic data from the Parkinson’s Progression Markers Initiative32 (Supplementary Table 2) In the AMP-PD data set, the CSF markers within the panel related to DLB (i.e., DDC, FCER2, CRH and MMP3) were all significantly dysregulated or showed nominal significance in both the prodromal and symptomatic phase of PD compared to controls (Fig. 5a). Here, FCER2 is linked to Lewy body dementia.