Amyloid precursor protein (APP), which has historically correlated strongly to Aβ accumulation in our proteomic datasets [20], was significantly elevated in both PDD (p = 0.0038, log2Δ = 0.18) and DLB (p = 4.15E-05, log2Δ = 0.39) but largely unaltered in PD (p = 0.98, log2Δ = 0.024), aligning with the moderate to severe CERAD scores of the dementia cases. This evidence concerns the gene APP and Parkinson disease.