Serum NFL strongly correlated with CSF NFL levels (<i>r</i> = 0.72, <i>p</i> < 0.0001) in all groups and with age in PD (<i>r</i> = 0.78, <i>p</i> < 0.0001) and controls (<i>r</i> = 0.66, <i>p</i> < 0.0001).
Here, we investigated whether CSF levels of catecholamines and its metabolites are altered in PD patients with LID [PD-LID, n = 8)] as compared to non-dyskinetic PD patients receiving l-DOPA (PD-L, n = 6), or not receiving l-DOPA (PD-N, n = 7) as well as non-PD controls (n = 16).
In patients with diabetes but without Parkinson disease, the presence of diabetes mellitus was associated with lower striatal dopamine transporter binding (<i>p</i> < 0.05) and higher tau (<i>p</i> < 0.05) and α-synuclein (<i>p</i> < 0.05) CSF levels compared to healthy controls.
CSF neurogranin levels were significantly lower in mild-to-moderate Parkinson's disease compared to controls, correlated with amyloid-<i>β</i> and <i>α</i>-synuclein, and with motor stage.