Relationship between uric acid and arterial stiffness in the elderly with metabolic syndrome components

BACKGROUND: High uric acid (UA) levels and metabolic syndrome (MS) are risk factors for atherosclerotic diseases. Brachial-ankle pulse wave velocity (baPWV) is a valid and reproducible measurement by which to assess arterial stiffness and a surrogate marker of atherosclerosis. However, little is known about the relationship between them, especially in elderly Chinese with MS components who are at high risk for atherosclerotic diseases. METHODS: One thousand and twenty Chinese subjects (159 women) older than 60 years of age (mean age (70.6 ± 5.7) years) with at least one MS component underwent routine laboratory tests, and baPWV measurements were analyzed. RESULTS: Participants were divided into four groups by MS components. The mean age did not significantly differ among the MS component groups. We found that not only the diagnostic factors (blood pressure, body mass index (BMI), lipids, glucose) of MS but also baPWV, UA, insulin, homeostasis model of assessment for insulin resistence index (HOMAIR) levels increased, and high density lipoprotein (HDL)-C decreased with an increased number of MS components (test for trend P < 0.05). The association between UA and baPWV was observed after adjustment for gender, age, blood pressure, BMI, serum creatinine and high density lipoprotein, and insulin resistance (r = 0.186, P < 0.0001). There were increases in the odds ratios for the association between the number of components of MS, UA and baPWV, even after adjustment for traditional risk factors. However, after adjustment for insulin or HOMA-IR, there were no significant differences in the multivariate odds ratios among the number of MS components for UA. CONCLUSIONS: The UA level is positively associated with baPWV and MS, but the association between UA and MS is dependent on insulin resistance. Furthermore, baPWV is independently associated with MS in our study population.