A Further Step in the Relationship between Uric Acid and Vascular Risk: Tubular Handling of Uric Acid in Hypertension Study

Abstract

Background: Uric acid poses a major risk to cardiovascular function which, in turn, increases the chances of kidney disease. This is not only an indication of renal damage, but also precipitates its development. We analyzed the kidney metabolism in hypertensive patients in order to establish any disparities compared to those of healthy individuals, and to ascertain if there were any changes in cases such as hypertension with chronic renal failure, including the use of diuretics in cases of obesity. Methods: We performed a descriptive, cross-sectional and retrospective study of 95 hypertensive patients to determine the parameters of renal excretion of uric acid. We compared the results of the hypertensive patients with the existing data of healthy individuals; examining the effects of chronic kidney disease - the administration of diuretics including cases of obesity - in the renal metabolism of uric acid. Results: The clearance of uric acid (5,56 ml/min) and its fractional excretion (6,65%) are lower in hypertensive people than in healthy individuals (UACl: 8-12 ml/min and UAEF: 8-10%). This clearance decreases significantly in hypertensive patients with chronic kidney disease compared to hypertensive patients with normal renal function (3.38 vs. 6.16 ml / min) including patients treated with diuretics (6.1 vs. 6.4 ml/min). Obesity also contributes to the reduction of renal excretion of uric acid. Conclusion: Renal excretion of uric acid is reduced in cases of hypertension with normal renal function and no diuretic therapy, in cases of chronic kidney disease and in treatment with diuretics. So, the question here is whether this could be the pathogenic basis for many forms of essential hypertension, or whether it is caused by the negative impact of hypertension in the kidney.