Renal vascular lesions in the elderly: nephrosclerosis or atheromatous renal disease?

Abstract

In white Europeans, renal size and function decline with age. This phenomenon has long been attributed to nephrosclerosis, i.e. primary vascular lesions associated with glomerular obsolescence, tubulointerstitial lesions and fibrosis. The part played by ageing and by pre-existing hypertension is still a matter of debate. Nephrosclerosis is a diagnosis of exclusion when no renal histology is available. As renal biopsy is rarely carried out in an elderly patient with atrophic kidneys, a long history of hypertension and only microalbuminuria or no proteinuria, the diagnosis of nephrosclerosis is generally overestimated. Even when renal histology is available, only subtle differences in vascular lesions have been claimed to distinguish those due to ageing from those due to hypertension. At any rate, meticulous control of blood pressure is certainly the most efficient means of protecting the renal vessels from further deterioration. Atheromatous renal disease has more recently been recognized as a major cause of progressive renal failure in the elderly. Renal artery stenoses due to atheromatous plaques might well be the cause of 10-15% of end-stage renal failure in whites aged > 50 and be the fourth cause of uraemia in this age group. Such stenoses are usually bilateral and developing. Present imaging methods, such as duplex ultrasound scanning and renal scintigraphy, are valuable means of diagnosis. Renal angioplasty can halt the the pace of renal insufficiency, or even durably improve it in nearly half of the cases. Finally, aorto-renal atheroma is a common and underestimated cause of cholesterol embolism. Minor, spontaneous forms thereof are indistinguishable from nephrosclerosis. Massive embolism entails a dismal prognosis, in terms of both renal function and patient survival. In conclusion, renal vascular lesions in the elderly remain a major concern. Improving non-invasive diagnostic procedures and applying preventative as well as curative measures should significantly reduce the incidence of end-stage renal disease is such patients.