Association of serum uric acid and non-motor symptoms in Parkinson's disease: A cross-sectional study from a movement disorders clinic in Lagos, Nigeria

Background and Objective: The role of serum uric acid (SUA) as a biomarker in Parkinson's disease (PD) remains exploratory and has not been described in our population. The objective of this study was to explore the profile of SUA and its relationship to nonmotor symptoms (NMS) burden in PD. Methods: This cross-sectional study recruited 70 persons with PD and 140 matched healthy controls in Lagos, Nigeria. PD was diagnosed using the United Kingdom PD Society Brain Bank criteria. NMS were assessed with the NMS Questionnaire (NMS-Quest). SUA was measured using standard methods. Results: The mean ages of PD and controls were 63 ± 9.4 years and 62.9 ± 8.8 years, respectively (P = 0.65), with no difference when compared by sex. The median PD duration (interquartile range [IQR]) was 4 (4.25) years. Median Hoehn and Yahr stage (IQR) was 2.5 (1.0). The mean total unified Parkinson's disease rating scale score was 70.7 ± 23.7. The mean NMS-Quest score was 8.5 ± 3.8. Mean SUA level was significantly lower in PD compared to controls (2.42 ± 0.75 mg/dL vs. 3.73 ± 1.09 mg/dL [P = 0.000]). There was a nonsignificant inverse linear trend of association (r = −0.184; P = 0.126) between the total NMS-Quest score and SUA level in PD. Logistic regression analysis revealed hyposmia and memory impairment were significantly related to lower SUA levels (P = 0.02 and P = 0.04, respectively). Conclusion: Our study corroborates the potential of SUA as a serum biomarker in PD and a possible role in defining non-motor symptom burden. Further exploration to clarify the association and interrogate the impact of interventions is warranted.