Serum and cerebrospinal fluid urate levels in synucleinopathies versus tauopathies

Background Low levels of serum urate are associated with a higher risk of Parkinson's disease (PD). Higher serum and cerebrospinal fluid (CSF) urate levels are associated with slower rates of clinical decline in PD and in multiple system atrophy (MSA). Aims To compare CSF and blood urate levels in healthy controls, patients with synucleinopathies and with tauopathies. Methods We investigated urate levels in serum and CSF from 18 healthy controls, 19 patients with synucleinopathies (six patients with PD and 13 with MSA), and 24 patients with tauopathies (18 with progressive supranuclear palsy and six with corticobasal degeneration). None of the patients were treated with dopaminergic medications. Results No significant differences were seen when comparing serum and CSF urate levels from controls across the parkinsonian diagnostic groups. However, in men, serum urate levels were significantly lower in the synucleinopathy group compared with the tauopathy group (P = 0.046), although with a broad overlap. Conclusion Our study suggests that urate levels might provide new insights into the potential pathophysiological mechanisms underlying Parkinsonism and thereby contribute to the future management of these disorders.