Lack of association between serum uric acid and organ damage in a never-treated essential hypertensive population at low prevalence of hyperuricemia

Background: It is still undefined whether serum uric acid (SUA) is an independent risk factor for target organ damage (TOD) and cardiovascular events in human hypertension. We sought to investigate the association of SUA with subclinical cardiac, vascular, and renal alterations in never-treated uncomplicated essential hypertensives. Methods: A total of 580 subjects with recently diagnosed (< 1 year) grade 1 and 2 hypertension, categorized by sex and tertiles of SUA levels, were considered for this analysis. All subjects underwent extensive clinical, laboratory, and ultrasonographic investigations searching for cardiac and extracardiac TOD. Results: Hyperuricemia (SUA > 7.0 mg/dL in men and > 6 mg/dL in women) was present in 8.3% of the patients. The overall prevalence of left-ventricular hypertrophy (LVH), carotid alterations, and microalbuminuria was 28%, 27%, and 8%, respectively. No differences in the prevalence rates of these TOD markers were present across all SUA tertiles in the entire population, as well as in both sexes. The SUA levels were similar in patients with and without LVH, carotid alterations, or microalbuminuria. When patients were classified according to the number of organs involved, those with multiple TOD (2 or 3 organs) had significantly higher SUA levels (5.1 +/- 1.3 or 5.2 +/- 1.4 mg/dL), as compared with those with a single or no organ involvement (4.9 +/- 1.3 or 4.9 +/- 1.4 mg/dL, P < .05). The association, however, between SUA levels and multiple TOD was not confirmed in a logistic regression analysis. Conclusions: Our findings do not support the role of SUA as an independent risk factor for subclinical TOD in a selected population of recently diagnosed uncomplicated hypertensives at low prevalence of hyperuricemia.