# The association between blood urea nitrogen to albumin ratio and cognitive function in Parkinson’s disease patients

## TL;DR

This study finds that higher blood urea nitrogen to albumin ratio is linked to worse cognitive function in Parkinson’s disease patients.

## Contribution

The study identifies BAR as a potential biomarker for cognitive decline in Parkinson’s disease.

## Key findings

- Higher BAR levels were significantly associated with lower MoCA scores in PD patients.
- BAR was negatively correlated with visuospatial and processing speed test scores.
- BAR showed a positive correlation with a measure of motor function impairment.

## Abstract

Cognitive impairment is a significant complication in Parkinson’s disease (PD), impacting quality of life and increasing caregiver burden. This study investigates the association between the blood urea nitrogen to albumin ratio (BAR) and cognitive impairment in PD patients, aiming to identify BAR as a potential biomarker for early detection and monitoring of cognitive decline.

Data from 1,312 PD patients were extracted from the PPMI database. The cognitive assessment tool was the Montreal Cognitive Assessment (MoCA) score and other cognitive metrics. The association between BAR and cognitive impairment was assessed using multivariate linear regression models to evaluate the continuous relationship, and logistic regression models to examine the binary outcomes. Furthermore, subgroup and sensitivity analyses were carried out to ensure the reliability of the results.

Higher BAR levels were significantly associated with lower MoCA scores in PD patients, independent of other confounding variables (β = −0.21, 95% CI = -0.35 ~ −0.07, p = 0.003). The odds ratio for cognitive impairment, defined by a MoCA score cutoff of 26, was 1.15 (95% CI: 1.02–1.30, p = 0.027). Further analysis revealed that BAR was negatively correlated with the Benton Judgment of Line Orientation MOANS Scale Score and the Symbol-Digit Modalities Test T-score, and positively correlated with the Trail Making Test Part A Reverse Z-score. These findings suggest that higher BAR levels are associated with poorer performance in visuospatial abilities, processing speed, and motor function.

This study underscores the potential utility of BAR as a biomarker for cognitive impairment in PD. Future prospective cohort studies are warranted to validate these findings and explore the potential of BAR in clinical practice.