Blood Urea Nitrogen, Creatinine and Proteinuria as Novel Biomarkers in Parkinson's Disease: Study

Parkinson's disease (PD) is a progressive neurodegenerative disorder affecting movement and quality of life in the elderly. The causes of PD remain unclear, though mitochondrial dysfunction, oxidative stress and neuroinflammation are implicated. Recent evidence suggests chronic conditions like chronic kidney disease (CKD) and related markers of renal dysfunction may be associated with higher PD risk.

A recent paper published in Neurology India by researchers in China analysed the correlation of PD with blood urea nitrogen, creatinine and proteinuria levels to assess their potential as predictive biomarkers.This retrospective study included 200 hospitalized PD patients diagnosed per 2015 MDS criteria along with 110 healthy controls. Medical history, demographics, and clinical rating scales were recorded. Blood samples were assessed for renal function markers - urea nitrogen, creatinine, and estimated glomerular filtration rate (eGFR). Urine protein level was measured. Comparative statistics were computed and multivariate logistic regression conducted to determine risk factors. Correlation analysis was performed between biomarker levels and PD severity scores.

The authors found that the PD group showed significantly higher creatinine, urea and proteinuria versus controls, while total cholesterol and LDL-cholesterol were lower. Adjusted multivariate regression revealed elevated urea nitrogen, creatinine and proteinuria levels were independent risk factors for PD. ROC analysis indicated urea nitrogen predicted PD onset with AUC 0.680, 75% sensitivity and 53% specificity at 4.97μmol/L threshold. Creatinine predicted at 63.5μmol/L with 53% sensitivity, 79% specificity and AUC 0.673. Positive correlations were observed between blood urea nitrogen and PD duration, Hoehn-Yahr stage, and UPDRS score (r=0.309-0.540). Similarly, creatinine levels correlated positively with clinical PD progression scores (r=0.139-0.320). The findings suggest these renal markers track with advancing disease.

The identification of modifiable risk factors like proteinuria, elevated creatinine and urea for PD development allows possibilities for early intervention and prevention. The ability to predict onset using easily measurable blood-based biomarkers aids diagnosis and prognostics. Renal dysfunction may relate to PD pathophysiology through vascular damage, inflammation and toxin buildup. 

The study summarises that impaired renal function markers – proteinuria, high creatinine and urea nitrogen levels correlate with increased PD risk as well as disease progression. These markers may serve as predictive biomarkers in at-risk elderly. The results warrant validation through larger randomized controlled trials. Early treatment of renal dysfunction may impact the occurrence and advancement of PD.

ReYang, Guang1,2; Wang, Ling Zhi1; Zhang, Rong1; Zhang, Xiao Yu1; Yu, Yue1; Ma, Hai Rong1,; He, Xiao Gang1,. Study on the Correlation between Blood Urea Nitrogen, Creatinine Level, Proteinuria and Parkinson's Disease. Neurology India 71(6):p 1217-1221, Nov–Dec 2023.

DOI: 10.4103/0028-3886.391388ference