It shows significantly negative correlations with the markers aSyn (-0.17, p<0.05), GFAP (-0,31, p<0.0001), NfL (-0.27, p<0.001), S100 (-0.18, p<0.01), sTREM2 (-0.19, p<0.01), YKL40 (-0.22, p<0.01), p-tau (-0.19, p<0.01), p-tau/a-beta (-0.30, p<0.0001) and t-tau/a-beta (-0.26, p<0.001), indicating that impaired cognitive function is associated with higher CSF levels in PD. This evidence concerns the gene NEFL and Parkinson disease.