Serum uric acid levels and freezing of gait in Parkinson’s disease

Uric acid (UA) is a natural antioxidant and iron scavenger in the human body, which has been hypothesized to exert an anti-oxidative effect in Parkinson’s disease (PD). This study aimed to investigate the relationship between serum UA levels and freezing of gait (FOG) in PD. A total of 321 Chinese PD patients with fasting serum UA evaluated were included in the cross-sectional study. Demographics, clinical features, and therapeutic regimen were collected. The Unified PD Rating Scale (UPDRS) III and Hoehn and Yahr (H and Y) stage were used to evaluate the severity of disease, and the Frontal Assessment Battery (FAB) and Montreal Cognitive Assessment (MoCA) scales were used to assess the cognitive function. Patients with FOG showed lower proportion of male, longer disease duration, lower body mass index, lower concentrations of serum UA, higher total levodopa equivalent daily dosage, higher UPDRS III score, greater median H and Y stage, lower scores of FAB and MoCA, and higher frequencies of motor fluctuation, dyskinesia, falls, and festination compared to patients without FOG (P < 0.05). The binary logistic regression model indicated that high UPDRS III score (OR = 1.049, P < 0.001), fluctuation (OR = 2.677, P = 0.035), dyskinesia (OR = 6.294, P = 0.003), festination (OR = 3.948, P < 0.001), falls (OR = 7.528, P < 0.001), and low serum UA levels (OR = 0.990, P < 0.001) were associated with FOG. Our study suggests that low serum UA concentration is associated with the occurrence of FOG in PD.