Salivary uric acid as a noninvasive biomarker of metabolic syndrome

Maria Soukup,Benmichael Idowu,Izabela Biesiada,Edward G Bridges,Kristie Grove Bridges,Derek Rodeback,Lance Ridpath,Aaron Henderson,Andrea M Nazar

doi:10.1186/1758-5996-4-14

Abstract

BackgroundElevated serum uric acid is associated with obesity, hypertension and metabolic syndrome. Because a linear relationship exists between serum and salivary uric acid (SUA) concentration, saliva testing may be a useful noninvasive approach for monitoring cardiometabolic risk. The goal of this pilot study was to determine if SUA is increased in patients with metabolic syndrome and to investigate correlations between SUA and individual cardiometabolic risk factors.FindingsVolunteers between the ages of 18 and 65 without conditions known to affect serum uric acid levels were recruited. Height, weight, blood pressure and waist circumference were measured and a full lipid panel along with fasting blood glucose was obtained. Saliva samples were collected and uric acid levels were determined. 78 volunteers, 35% of whom had metabolic syndrome, completed the study. SUA was significantly elevated in patients with metabolic syndrome (p=.002). The incidence of metabolic syndrome in the 4th quartile for SUA was 67% compared to 25% in quartiles1-3 combined. Significant correlations were seen between SUA and systolic blood pressure (r=.440, p=.000), diastolic blood pressure ( r=.304, p=.007), waist circumference (r=.332, p=.003), BMI ( r=.269, p=.018), fasting blood glucose ( r=.341, p=.002), triglycerides (r=.410, p=.000), HDL ( r=.237, p=.036) and the number of cardiometabolic risk factors present (r=0.257, p=.023).ConclusionsThese results suggest that SUA may be a useful biomarker for noninvasive monitoring of cardiometabolic risk. Larger studies are needed to validate this approach.

Highlights

Elevated serum uric acid is associated with obesity, hypertension and metabolic syndrome
These results suggest that salivary uric acid (SUA) may be a useful biomarker for noninvasive monitoring of cardiometabolic risk
The enzyme responsible for its production generates free radicals and several studies have shown that uric acid can act as a pro-inflammatory and pro-oxidant agent [reviewed in 10]. Regardless of whether it plays a causative role or is an indicator of metabolic disturbances, uric acid may be a useful biomarker for identifying high risk patients and monitoring the response to lifestyle interventions. The purpose of this pilot study was to investigate the feasibility of a noninvasive approach by determining if salivary uric acid is elevated in adults with metabolic syndrome

Summary

Introduction

Elevated serum uric acid is associated with obesity, hypertension and metabolic syndrome. While numerous studies have demonstrated an association between serum uric acid, metabolic syndrome and cardiovascular disease risk, its role is not well understood [reviewed in 9,10]. Regardless of whether it plays a causative role or is an indicator of metabolic disturbances, uric acid may be a useful biomarker for identifying high risk patients and monitoring the response to lifestyle interventions.

Results

Conclusion