Renal vascular changes in renal disease independent of hypertension

Introduction. Cardiovascular disease is common in patients with renal disea se, but little is known about the effect of renal disease and loss of renal function on vascular morphology. Intima proliferation of small renal arter ies, which correlates with atherosclerosis in the aorta, is sometimes prese nt in renal disease and has been shown to increase with age and hypertensio n. We studied the effect of chronic renal disease and renal function, indep endent of hypertension, on intima proliferation. Methods. We retrospectively selected renal biopsies of subjects in whom a g lomerular filtration rate (GFR) measurement with [ II iothalamate;had been performed. To separate the effects of renal disease and renal function, we selected biopsies from (A) normotensive controls undergoing nephrectomy bec ause of renal carcinomas; (B) normotensive patients with renal disease and GFR > 90 ml/min; (C) normotensive patients with GFR 30-90 ml/min, and (D) h ypertensive patients with a GFR<90 ml/min. The area of the arteriolar lumen , intima, and media were measured. Results. No significant changes from control subjects were observed in grou p B. Intima proliferation was observed when renal function declined (intima /total vessel surface ratio was 0.262+/-0.071 in group C, 0.192 +/- 0.032 i n group A, and 0.205 +/- 0.035 in group B, P<0.05). The intima proliferatio n was aggravated in patients with renal insufficiency and hypertension (0.3 33 +/- 0.121, P< 0.05). Media surface area was not different between groups . Conclusion. Renal disease with preserved GFR does not cause significant int ima proliferation of small renal arteries. Loss of renal function is accomp anied by intima proliferation, even in the absence of systemic hypertension .