The kidney and cardiovascular risk.

Key words: arterial hypertension; renal function; failure in 18%, of a series of 500 patients followed until death by this author [7 ]. With the advent of antihyper-proteinuria; microalbuminuria; nephrosclerosis; anti-hypertensive therapy tensive therapy the cardiovascular prognosis of hyper-tensive patients improved dramatically, and renal prognosis has been considered by some authors as excellent when arterial hypertension is treated, with Introduction only a very small percentage of patients (<2%) developing chronic renal failure [8,9]. However, some pieces of evidence indicate that the prognosis of renal function A defective capacity to handle the sodium content in is not so good in essential hypertensive patients; among the diet seems to be the mechanism underlying a renal these are the increasing prevalence of nephrosclerosis origin of arterial hypertension [1]. Different theories as a cause of end-stage renal failure in patients entering have tried to explain this mechanism, but the most dialysis programmes in both US and Europe [10,11], plausible cause for the derangement in the renal capa-the existence of a progressive decline in renal function city to excrete sodium is the presence, from the very in a significant percentage of treated hypertensive early stages of the process, of renal vasoconstriction patients [12–14], the association between blood pres-that facilitates sodium retention [2 ]. This vasoconstric-sure and serum creatinine consistent with the possibility tion probably does not represent an intrinsic renal that blood pressure elevations even below the hyper-defect, but is the renal consequence of the systemic tensive range may induce early renal damage [15], the vascular adaptation to the hypertensive process [3]. description that in the United States one in 13 persons This possibility does not exclude the pivotal role of (7.7%) with hypertension will develop hypercreatininae-the kidney in the development of hypertension, neither mia [16 ], and finally the presence of proteinuria in does it exclude the hypothesis that the increase in percentages oscillating between 4 and 16% in different blood pressure is needed to maintain glomerular filtra-series of treated hypertensive patients [17 ]. All these tion rate and sodium excretion within normal limits arguments indicate that renal damage is still prevalent [4 ]. Interestingly, renal vasoconstriction is functional in essential hypertension, even considering that serum in the initial stages of the disease and remains constant creatinine is a poor method of estimating the evolution thereafter as a consequence of the nephrosclerosis of renal function, specially in the initial stages of chronic secondary to …