Increased renal resistive index in atherosclerosis and diabetic nephropathy assessed by Doppler sonography.
OBJECTIVE
The renal resistive index (RI) and pulsatility index (PI), measured using Doppler ultrasonography, reflect intrarenal vascular resistance. We evaluated the relationship between these indices and pulse wave velocity (PWV), a measure of arterial stiffness, which reflects atherosclerosis, and determined whether renal RI and PI differ depending on the underlying renal disease.


METHODS
A total of 245 inpatients with or without renal impairment who underwent ultrasonographic assessment of the renal artery were enrolled in the study. Patients with renal artery stenosis or severe renal failure (serum creatinine>or=6 mg/dl) were excluded from the study.


RESULTS
In univariate analysis, the RI and PI of the main renal arteries and the interlobar arteries were significantly correlated with PWV. Multivariate analyses showed that PWV was independently associated with the RI of the main renal arteries (P<0.01, R=0.256). Patients with a creatinine level less than 3 mg/dl were divided into a control group without renal diseases and three groups with different underlying renal diseases: diabetic nephropathy, chronic glomerulonephritis, and nephrosclerosis. The RI and PI of the main renal arteries and the interlobar arteries were significantly higher in patients with diabetic nephropathy than in the other three groups, even after adjusting for multiple variables, including creatinine clearance.


CONCLUSIONS
These results suggest that the increased RI of the renal arteries is associated with the severity of systemic atherosclerosis. Furthermore, the intrarenal vascular resistance differs depending on the underlying renal disease, and appears to increase to a greater extent in diabetic nephropathy.
Ohta
Yuko
Y
Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan. yukoo@intmed2.med.kyushu-u.ac.jp
Fujii
Koji
K
Arima
Hisatomi
H
Matsumura
Kiyoshi
K
Tsuchihashi
Takuya
T
Tokumoto
Masanori
M
Tsuruya
Kazuhiko
K
Kanai
Hidetoshi
H
Iwase
Masanori
M
Hirakata
Hideki
H
Iida
Mitsuo
M
D000328:Adult; D000368:Aged; D050197:Atherosclerosis / Q000503:physiopathology*; D001783:Blood Flow Velocity; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D002784:Cholesterol / Q000097:blood; D003928:Diabetic Nephropathies / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007668:Kidney / Q000098:blood supply* / Q000000981:diagnostic imaging; D007674:Kidney Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011673:Pulsatile Flow; D012077:Renal Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D018608:Ultrasonography, Doppler / Q000379:methods*
D001786:Blood Glucose; D002784:Cholesterol