A novel oxidative-inflammatory biomarker for Parkinson's disease: clinical utility of the uric acid-to-albumin ratio.

BACKGROUND

Emerging evidence highlights the contribution of systemic inflammation and oxidative stress to the pathogenesis and progression of Parkinson's disease (PD). Accordingly, blood-based biomarkers that capture these processes are of increasing clinical interest. This study evaluated the association between PD and serum uric acid, serum albumin, and their integrated index-the uric acid-to-albumin ratio (UAR)-to determine their potential utility as biomarkers of systemic inflammation, oxidative stress, and disease progression.

METHODS

A total of 153 patients with PD and 291 healthy controls were included. Serum uric acid, albumin, and UAR were measured through standardized biochemical assays. Group comparisons and multivariable logistic regression were performed to assess associations with PD, and analyses stratified by Hoehn and Yahr stage examined relationships with disease severity.

RESULTS

Uric acid, albumin, and UAR levels were significantly lower in patients with PD compared with healthy controls (all p < 0.001). After adjustment for age, sex, hypertension, and diabetes, UAR remained independently associated with PD, with lower UAR corresponding to higher odds of disease (OR = 0.72, 95% CI: 0.63-0.82, p < 0.001). Stratified analyses showed that UAR reductions were most prominent in early and middle PD stages, whereas advanced-stage values approximated those of controls. ROC analysis demonstrated moderate discriminative ability of UAR for PD overall (AUC = 0.630) and for early-to-middle stage disease (AUC = 0.620 and 0.644, respectively).

CONCLUSION

UAR is significantly reduced in PD and associated with early-middle disease stages, supporting its potential as an accessible biomarker for PD monitoring, though larger longitudinal studies are needed for validation.