Uric acid (UA) is independently associated with the emergence of hypertension. Nocturnal nondipping pattern of hypertension is associated with a greater risk of cardiovascular, renal, and cerebrovascular complications than dippers. The aim of the present study was to evaluate the relationship between the circadian blood pressure rhythm and UA level in patients with newly diagnosed essential hypertension. The study included 112 essential hypertensive patients and 50 healthy controls. The hypertensive patients were divided into two groups according to the results of 24‐hour ambulatory blood pressure monitoring, including 60 dippers (35 men, 25 women; mean age, 52.6±15.8 years) and 52 nondippers (29 men, 23 women; mean age, 55.9±13.2 years). Nondippers had significantly higher serum UA levels than the dippers and controls (5.8±0.8, 5.1±0.9 and 4.2±0.9 mg/dL, respectively; P<.001). Serum high‐sensitivity C‐reactive protein levels were also significantly higher in the nondipper group than the other groups (P<.001) and significantly correlated with serum UA (r=0.358, P<.001). Multivariate logistic regression analysis revealed an independent positive association between serum UA levels and nondipper pattern (odds ratio, 2.28; 95% confidence interval, 1.33–3.94; P=.003). Serum UA is strongly and independently associated with the nondipper circadian pattern in essential hypertension.
Background Serum uric acid (SUA) is associated with microvascular disease that could alter coronary blood flow and prognosis. We evaluated the effects of admission SUA levels on coronary blood flow and prognosis in 185 consecutive patients with ST-segment elevation myocardial infarction (STEMI) who underwent acute primary percutaneous coronary intervention (PCI). Methods Patients undergoing PCI for an acute STEMI were stratified into elevated SUA (>6.5 mg/dL) and normal SUA group (≤6.5 mg/dL). Primary end points were post-PCI myocardial blood flow and in-hospital and 1-year mortality. Results Serum uric acid level was high in 45 patients (24%) on admission. Subjects with elevated SUA had a higher prevalence of hypertension, previous myocardial infarction, multivessel disease, and Killip functional class III or higher. Corrected thrombolysis in myocardial infarction (TIMI) frame count was longer, and mean TIMI myocardial perfusion grade was higher in patients with elevated uric acid compared with controls. Patients with elevated SUA levels had higher in-hospital (6.6% vs 2.8%, P < 0.01) and 1-year mortality (11.1% vs 5.7%, P < 0.01). Major adverse cardiac events were higher in patients with elevated SUA levels both in-hospital (11.1% vs 5.7%, P < 0.01) and at 1 year (17.7% vs 10%, P < 0.05). An elevated admission SUA level also independently predicted both 1-year mortality (odds ratio, 1.41; 95% confidence interval, 1.24-2.69) and abnormal myocardial perfusion detected by TIMI myocardial perfusion grade in STEMI patients undergoing primary PCI (odds ratio, 2.14; 95% confidence interval, 1.17-4.19, respectively). Conclusions Elevated SUA level on admission independently predicts impaired myocardial flow and poor prognosis in STEMI patients undergoing primary PCI.