Renal resistance index is a marker of future renal dysfunction in patients with essential hypertension.
OBJECTIVE
In patients with essential hypertension (EHT), the intrarenal resistance index (RI) has been shown to be related to the severity of target organ damage (TOD). Cystatin C is has been reported to be related to TOD in EHT. The aim of the present study was to clarify whether the RI predicts future renal function assessed by cystatin C levels in EHT.


METHODS
One-hundred and twelve patients participated. RI and cystatin C were measured at baseline, and 12 months later, cystatin C was measured again.


RESULTS
The patients were divided into 2 groups according to RI value: the low RI group (RI<0.7) and the high RI group (RI> or =0.7). After 12 months, cystatin C levels were significantly elevated in the high RI group, whereas the levels remained unchanged in the low RI group. Stepwise regression analysis using the baseline values of RI, age, pulse pressure, HbA1c, cystatin C, log-transformed (ln) C-reactive protein and ln urinary albumin/creatinine as covariates, showed baseline RI was the only independent determinant of the time-related changes in cystatin C levels.


CONCLUSIONS
This finding suggests that the renal RI may be a marker of future renal dysfunction in EHT.
Okura
Takafumi
T
Department of Integrated Medicine and Informatics, Ehime University Graduate School of Medicine, Toon City, Ehime - Japan. okura@m.ehime-u.ac.jp
Kurata
Mie
M
Irita
Jun
J
Enomoto
Daijiro
D
Jotoku
Masanori
M
Nagao
Tomoaki
T
Koresawa
Mitsuko
M
Kojima
Shiho
S
Hamano
Yasuyuki
Y
Mashiba
Shinichi
S
Miyoshi
Ken-Ichi
K
Higaki
Jitsuo
J
D000367:Age Factors; D000368:Aged; D000419:Albuminuria / Q000209:etiology / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001794:Blood Pressure; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000097:blood; D018450:Disease Progression; D005260:Female; D005919:Glomerular Filtration Rate; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007668:Kidney / Q000098:blood supply*; D007674:Kidney Diseases / Q000097:blood / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012044:Regression Analysis; D012079:Renal Circulation; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D018616:Ultrasonography, Doppler, Duplex; D014655:Vascular Resistance
D015415:Biomarkers; D003404:Creatinine; D055316:Cystatin C; D006442:Glycated Hemoglobin; C525030:CST3 protein, human; C517652:hemoglobin A1c protein, human