CSF markers of neurodegeneration in Parkinson's disease

Parkinson's disease (PD) is a chronic, progressive, neurodegenerative disease with a multifactorial etiology. Protein accumulation is speculated by some to play a prominent role in the pathogenesis of PD. The severity of neurodegeneration should correlate with cerebrospinal fluid (CSF) levels of these neurodegenerative markers (NDMs). The aims of the study were to assess the CSF levels of tau protein, beta-amyloid (1-42), cystatin C, and clusterin in patients suffering from PD and in a control group, to compare the CSF levels between the two groups and to correlate them to PD duration. NDMs in the CSF were assessed in 32 patients suffering from PD and in a control group (CG) of 30 patients. The following statistically significant differences in the CSF were found: higher tau protein (p = 0.045) and clusterin levels (p = 0.004) in PD patients versus CG; higher tau protein levels (p = 0.033), tau protein/beta-amyloid (1-42) ratio (p = 0.011), and clusterin (p = 0.044) in patients suffering from PD for <2 years versus patients suffering PD for more than 2 years. No differences between beta-amyloid (1-42) and cystatin C CSF levels were found in the CG and PD patients groups. Significantly higher tau protein and clusterin CSF levels in the group of PD patients with disease duration of <2 years probably reflect the fact that most neurodegenerative changes in PD patients occur in the initial stage of disease.