Abstract 5414: Serum Uric Acid Levels versus the Abdominal Obesity in Relation to Incident Hypertension in a Prospective Study in a Chinese Community

Abstract

BACKGROUND: Most Caucasian-based epidemiological data have shown that hyperuricemia is associated with the risk of hypertension, but whether this association is independent of adiposity and other vascular risk factors remains unclear. Therefore, we evaluated the associations of serum uric acid versus abdominal obesity with incident hypertension in a large Chinese Han population. METHODS: We conducted a community-based prospective cohort study comprising 7220 participants (mean age 37 years; 74% men) in the Qingdao Health and Nutrition Examination Survey in China, who were free from hypertension at study entry in 1999–2000. During 4-year follow-up, 1370 men (19.0%) and 208 women (11.0%) had developed hypertension. RESULTS: After adjustment for age, body mass index, waist circumference, and other covariates, the relative risks (RR) of developing hypertension according to uric acid quartiles were 0.97, 1.23, and 1.39 [95% confidence interval (CI), 1.16–1.68; P trend=0.008] for men and 1.49, 1.58, 1.85 (95%CI, 1.06–3.24; P trend=0.007) for women. The associations of hypertension with serum uric acid increased with the component number of metabolic syndrome (none, one, two, or more), which is defined by the criteria of the modified Adult Treatment Panel III and an Asian-specific waist circumference cut-off point (≥90 cm in men, ≥80 in women). Given that abdominal obesity is an important underlying risk factor for metabolic syndrome, in joint analyses of waist circumference and serum uric acid, participants with abdominal obesity had a consistently higher risk than those without. Compared with those in the lowest uric acid quartile and without abdominal obesity, participants who were in the highest quartile and also had abdominal obesity had a 3.0-fold and 3.4-fold greater risk of incident hypertension in men (95%CI, 1.56–2.97) and in women (95%CI, 2.10–3.81), respectively. To minimize the bias from reverse causality due to subclinical hypertension, analyses after excluding the first 2 years of follow-up showed similar results. CONCLUSIONS: These data suggest a positive association between serum uric acid and incident hypertension during short-term follow-up in a Chinese population. The association was partly mediated through abdominal obesity. 1