RESUMO
Systemic Sclerosis (SSc) is an autoimmune disorder characterized by organ and tissue fibrosis in which the incidence of atherosclerosis and cardiovascular events is increased, although the exact underlying mechanism remains unclear. Arterial stiffness is a marker of vascular damage that can predict cardiovascular events; therefore, this study aimed to assess the augmentation index (AIx) and pulse wave velocity (PWV), markers of stiffness, in a Systemic Sclerosis population and to detect potentially associated variables. Fourteen female Systemic Sclerosis patients and 14 age- and sex-matched controls were enrolled. Demographic, anthropometric, sero-hematological parameters and disease characteristics were collected for each participant. Arterial stiffness was evaluated using an applanation tonometry system. No differences were found between groups, except for BMI, fasting blood glucose, red blood cells count, hemoglobin, and treatment. Patients had increased augmentation index than the controls (p = 0.008). PWV was significantly decreased in SSc patients compared with the controls (p = 0.007). PWV was correlated with age (r = 0.462; p = 0.048) and BMI (r = 0.458; p = 0.050). Finally, patients with no specific auto-antibody pattern had greater AIx than those expressing anticentromere antibodies. Our study demonstrated that SSc patients had greater AIx, but lower PWV than the controls. In addition, few variables were correlated to arterial stiffness. Further studies are necessary to validate these findings and to establish medication's role in modifying cardiovascular risk.
RESUMO
Increased levels of uric acid (UA) have been shown to be correlated with many clinical conditions. Uric acid may adversely affect the insulin signalling pathway inducing insulin resistance (IR). Several studies report the association between arterial stiffness (AS), an early indicator of atherosclerosis, and UA. The purpose of the present study was to evaluate the association between UA and AS, considering the potential role of IR. We enrolled 1114 newly diagnosed, never-treated hypertensive patients. Insulin resistance was assessed by the homeostatic model assessment (HOMA) index. Arterial stiffness was evaluated as the measurement of the carotid-femoral pulse wave velocity (PWV). The study cohort was divided into subgroups, according to increasing tertiles of UA. The mean values of UA were 5.2 ± 1.6 mg/dL in the overall population. Pulse wave velocity was linearly correlated with UA (p < 0.0001), HOMA (p < 0.0001), high sensitivity C-reactive protein (p < 0.0001), systolic blood pressure (p < 0.0001) and LDL cholesterol (p = 0.005). Uric acid was the strongest predictor of PWV and was associated with the highest risk for increased AS. The interaction analysis showed that the joint effect of increased UA and HOMA was significantly higher than that expected in the absence of interaction under the additive model, indicating that the two biomarkers synergically interacted for promoting vascular damage. Our data showed that UA interacted with IR to increase AS in a large cohort of newly diagnosed, never-treated hypertensive patients.