Relationship between Serum Uric Acid Concentration, Metabolic Syndrome and Carotid Atherosclerosis

Abstract
Objective: Carotid intima-media thickness (IMT) is a useful surrogate marker of cardiovascular disease. Associations between hyperuricemia, metabolic syndrome and carotid IMT have been reported, but few of the studies have been conducted in a Japanese population. Methods: A total of 1,128 subjects (498 men aged, 68±14 years and 630 women aged 72±12 years) were divided into 4 groups according to serum uric acid (SUA) quartiles. We first investigated the association between SUA concentrations and metabolic syndrome; then, we assessed whether there is an independent association of SUA with carotid IMT in a population subdivided according to gender and metabolic syndrome status. Results: In women, the prevalence of visceral obesity and metabolic syndrome were significantly increased with increased SUA quartiles, but not in men. After adjusting for age, smoking status, LDL-cholesterol, creatinine and history of diabetes mellitus, the odds ratios (95% CI) of sex-specific quartiles of SUA for metabolic syndrome were 1.0, 1.37 (0.79-2.37), 1.37 (0.79-2.38), and 1.80 (1.03-3.15) in men, and 1.0, 1.04 (0.56-1.94), 2.35 (1.30-4.22), and 2.20 (1.16-4.20) in women. After adjusting for various known risk factors, the prevalence of carotid atherosclerosis (IMT≥1.0 mm) was higher in subjects in the second, third and fourth quartiles of SUA concentration with odds ratios (95% CI) of 2.41 (1.08-5.37), 3.33 (1.49-7.42), and 2.73 (1.17-6.35), respectively in men without metabolic syndrome but not in men with metabolic syndrome or in women with or without metabolic syndrome. Conclusion: The prevalence of metabolic syndrome was significantly increased according to SUA values only in women. In men without metabolic syndrome, SUA was found to be an independent risk factor for incidence of carotid atherosclerosis.