Accelerated decline in renal perfusion with aging in essential hypertension.

Abstract

The present cross-sectional study was designed to assess the effect of the severity of hypertensive cardiovascular disease and age on renal hemodynamics. In a homogeneous population of 157 white men (aged 15 to 87 years), we assessed renal and systemic hemodynamics by measuring mean arterial pressure invasively, renal blood flow by 131 Ipara-aminohippuric acid clearance, and cardiac output by the indocyanine dye dilution technique. Stepwise multiple regression analysis revealed the following independent determinants of renal blood flow: age (/3=-.42, P<.001), height O = + .14, P<.03), mean arterial pressure (/3= -.15, P<.02), and cardiac output (/3=+.19, P<.008). Renal blood flow corrected for height correlated inversely with age in all three groups. However, the renal fraction of cardiac output S tructural changes in the vascular bed of the kidneys caused by arterial hypertension, termed arteriolar nephrosclerosis, have been found to correlate with similar changes in the retina, pancreas, and salivary glands but nevertheless do occur more frequently and extensively in the kidneys than in any other organ.1 Studies of end-stage renal disease showed that hypertension accounted for 15% to 20% of all cases of renal failure in the United States, a percentage that increased to 30% of cases of renal failure in minority populations. 24 In a previous report on the natural history of essential hypertension (at a time when high blood pressure frequently remained untreated), 18% of 350 patients had evidence of impaired renal function that led to end-stage renal disease in 12%. 5At necropsy, 68% to 97% of patients with well-established hypertension had histologicalry proven renal arteriosclerosis.6 -7 The severity of arteriolar renal involvement appeared to be determined by the severity of hypertensive disease. 6 The degree of the renal vascular involvement, either structural or functional, was closely correlated with the reduction in renal blood flow. 8 ' 9 A subsequent study using selective renal arteriography confirmed a good corReceived July 14, 1993; accepted in revised form December 3, 1993.From the Department of Medicine IV, University of ErlangenNurnberg (Germany) (R.E.S.); the Department of Medicine, University of Bonn, Bonn-Venusberg, Germany (H.S.); and the Department of Internal Medicine, Section on Hypertensive Diseases, Ochsner Clinic and Alton Ochsner Medical Foundation, New Orleans, La (F.H.M.).This manuscript, in which one of the authors (F.H.M.) is from the Alton Ochsner Medical Foundation, was sent to the previous Hypertension editorial office at the University of Iowa for review by expert referees, for editorial decision, and for final disposition.Reprint requests to Dr Roland E. Schmieder, 4. Medizinische Klinik/Nephrologie, University of Erlangen-Nurnberg, Kontumazgarten 14-18, D-8500 Nurnberg 80, FRG.did not correlate with age in borderline hypertension (r=.17, P=NS) and in normotension (r=.12, P=NS), suggesting a parallel decline in renal blood flow and cardiac output with aging. In contrast,...

Non-invasive Blood Pressure Measurements in Cats: Clinical Significance of Hypertension Associated with Chronic Renal Failure.

“…In humans, it is already well known that blood pressure rises concomitant with an increase in age [14]. Bodey and Michell [2] also indicated a correlation between blood pressure and age in dogs.…”

Asymmetric Dimethylarginine, Blood Pressure, and Renal Perfusion in Elderly Subjects

“…It is well known that even normal aging is associated with some loss of renal tissue accompanied by changes in renal hemodynamics. 15 The observed decrease in ERPF and increase in FF and RVR is particularly pronounced in elderly persons with cardiovascular comorbidity such as hypertension and/or heart failure, 14,20,21 that is, conditions in which the availability of NO is reduced. 1 In this context, it has not been resolved whether age-related changes in renal hemodynamics are caused by structural abnormalities or whether there exists a functional abnormality as well, for example, reduced capacity of renal vessels to dilate as a consequence of reduced availability of (or responsiveness to) vasodilator substances.…”

A Clinical Evaluation of Blood Pressure through Non-Invasive Measurement Using the Oscillometric Procedure in Conscious Dogs.

“…It is known that blood pressure increases with age in humans. This is thought to be caused by a reduction in vascular compliance and changes in renal vascular resistance due to a reduction in the amount of renal blood flow with age [16,22]. No detailed examination has been conducted on dogs, but there are reports that identify a similar tendency [2].…”