ABC | Volume 111, Nº6, December 2018

Original Article Serum Uric Acid Levels are Associated with Cardiometabolic Risk Factors in Healthy Young and Middle-Aged Adults Thaís da Silva Ferreira, 1,2 Julia Freitas Rodrigues Fernandes, 2 Luciene da Silva Araújo, 2 Lívia de Paula Nogueira, 2 Priscila Mansur Leal, 2 Vanessa Parada Antunes, 2 Maria de Lourdes Guimarães Rodrigues, 2 Debora Cristina Torres Valença, 2 Sergio Emanuel Kaiser, 2 Márcia Regina Simas Torres Klein 2 Universidade Federal do Estado do Rio de Janeiro (UNIRIO), 1 Rio de Janeiro, RJ - Brazil Universidade do Estado do Rio de Janeiro (UERJ), 2 Rio de Janeiro, RJ - Brazil Mailing Address: Thaís da Silva Ferreira • Avenida Pasteur, 296 Prédio da Escola de Nutrição, Departamento de Nutrição Aplicada. Postal Code 22290-240, Urca, Rio de Janeiro, RJ – Brazil E-mail: thaissferreira@gmail.com , thais.ferreira@unirio.br Manuscript received May 11, 2018, revised manuscript June 19, 2018, accepted July 02, 2018 DOI: 10.5935/abc.20180197 Abstract Background: Observational studies have highlighted an association between serum uric acid (SUA) levels and cardiovascular risk factors. Despite the growing body of evidences, several studies were conducted in older individuals or in carriers of diseases susceptible to affect SUA levels and cardiometabolic risk markers. Objective: To evaluate the relationship of SUA with body adiposity, metabolic profile, oxidative stress, inflammatory biomarkers, blood pressure and endothelial function in healthy young and middle-aged adults. Methods: 149 Brazilian adults aged 20-55 years, both sexes, underwent evaluation of body adiposity, SUA, fasting glucose and insulin, lipid profile, malondialdehyde (MDA), high sensitivity C-reactive protein (hs-CRP), adiponectin, blood pressure and endothelial function. Endothelial function was assessed by the reactive hyperemia index (RHI) derived from peripheral arterial tonometry method. Participants were allocated in two groups according to SUA levels: control group (CG; n = 130; men ≤ 7 mg/dL, women ≤ 6 mg/dL) and hyperuricemia group (HG; n = 19; men > 7 mg/dL, women > 6 mg/dL). A P-value < 0.05 was considered statistically significant. Results: After adjustment for confounders, participants in HG compared with those in CG displayed higher body mass index (BMI): 34.15(33.36-37.19) vs.31.80 (26.26-34.42) kg/m 2 ,p = 0.008, higher MDA: 4.67(4.03-5.30) vs. 3.53(3.10‑4.07) ng/mL, p < 0.0001 and lower RHI: 1.68 ± 0.30 vs. 2.05 ± 0.46, p = 0.03). In correlation analysis adjusted for confounders, SUA was positively associated (p < 0.05) with BMI, waist circumference, LDL-cholesterol, triglycerides and MDA, and negatively associated (p < 0.05) with HDL-cholesterol, adiponectin and RHI. Conclusions: This study suggests that in healthy young and middle-aged adults higher SUA levels are associated with higher body adiposity, unfavorable lipid and inflammatory phenotype, higher oxidative stress and impaired endothelial function. (Arq Bras Cardiol. 2018; 111(6):833-840) Keywords: Uric Acid/metabolism; Oxidative Stress; Inflammation; Endothelium/ dysfunction; Adults. Introduction Cardiovascular diseases (CVD) are the leading causes of death in the world. According to World Health Organization, ischemic heart disease and stroke together accounted for 15 million deaths in 2015. 1 Therefore, it is important to identify early and cost-effective markers of CVD risk. Uric acid is the final product of endogenous and dietary purine metabolism. 2 In several cross-sectional and longitudinal observational studies, elevated serum uric acid (SUA) levels have been associated with increased risk for cardiovascular events and mortality, as well as with cardiovascular risk factors such as hypertension, obesity, metabolic syndrome, insulin resistance and dyslipidemia. 3 Increased SUA concentration has also been positively correlated with surrogate markers of CVD: impaired endothelial function, increased carotid intima‑media thickness and aortic stiffness. 4-11 It is noteworthy that the majority of the studies aimed at evaluating the relationship of SUA with vascular function and/or cardiometabolic markers were conducted in postmenopausal women, older individuals and/or in individuals with renal impairment or CVD risk factors (ex. hypertension and diabetes). 3,5-11 Therefore, the participants included in many previous studies were more likely affected by a compromised cardiocirculatory and/or metabolic status which would represent a confounding factor in the association between SUA and cardiometabolic risk factors. The purpose of this study was to evaluate the relationship of SUA with body adiposity, metabolic profile, inflammatory biomarkers, oxidative stress, blood pressure and endothelial function in a sample of healthy young and middle-aged adults. 833