Renal resistivity index is inversely proportional to estimated glomerular filtration rate in chronic kidney disease

ABSTRACT

Background: Renal resistive index (RRI) measured by Doppler ultrasonography has been associated with severity, rate of progression and mortality in chronic renal failure. Parameters like renal vascular resistance, filtration fraction and effective renal plasma flow have been associated with renal resistivity index in chronic kidney disease patients.Methods: This hospital based cross-sectional study was conducted from April 2016 to August 2017. 100 patients with chronic kidney disease were enrolled. RRI was calculated from the blood flow velocities observed during Doppler examinations of the segmental arteries and estimated glomerular filtration rate (eGFR) was calculated using the chronic kidney disease epidemiology collaboration (CKD-EPI) equation. Spearman Rank-Order Correlation Coefficient was used.Results: A Significant inverse correlation was observed between RRI and eGFR (r= -0.347, p =0.0004). It was also observed that older age (r= 0.297), higher systolic blood pressure (r= 0.365), lower levels of hemoglobin (r= -0.34 for males and r= -0.353 for females) were observed to correlate with higher values of RRI in advanced CKD stages.Conclusions: RRI correlated inversely with eGFR in chronic kidney disease and hence was directly related to the severity of the disease.