Uric acid, metabolic syndrome and atherosclerosis: the chicken or the egg, which comes first?

Background: A great debate in literature exists nowadays on the role of uric acid as a marker of cardiovascular and metabolic organ damage or a risk factor for cardiovascular and metabolic disease. Methods: The study aimed to determine the relationship among serum uric acid and metabolic syndrome and atherosclerosis, by means of carotid intima media-thickness, in a cohort of 811 otherwise healthy overweight/obese subjects, without overt atherosclerosis not using any kind of drug. Results: Uric acid levels were positively related to male gender, waist circumference, BMI, systolic and diastolic pressure levels, fasting insulin, fasting glucose, HOMA-IR, triglycerides, total cholesterol, LDL cholesterol, the presence of metabolic syndrome and the number of the components of metabolic syndrome and negatively related to HDL cholesterol levels. No correlation was found between uric acid and carotid intima media thickness. At the multiple regression analysis, only waist circumference and triglycerides (positively) and HDL-cholesterol (negatively) maintained an independent association with uric acid as dependent variable, while age, female gender and uric acid showed a significant independent association with metabolic syndrome as dependent variable. Moreover, the analysis of the odd ratios showed that the risk of developing metabolic syndrome was consistent with uric acid levels ranging from 3 mg/dl to 8 mg/dl. Conclusion: The presence of metabolic syndrome does not seem to provide hyperuricemia. By contrast, higher serum uric acid level may predict the risk of metabolic syndrome. Moreover, our results suggest that uric acid cannot be considered a risk factor for early atherosclerosis, at least when assessed using carotid ultrasound.