A renal arterial resistance index ≥80 predicted worsening renal function, with overt proteinuria developing in 24% of patients with an index ≥80 compared to 5% with an index <80 (P<0.01).
Cohort (n=157)
Does a renal arterial resistance index ≥ 80 predict worsening renal function in microalbuminuric, hypertensive, type 2 diabetic patients?
Intrarenal arterial resistance index ≥ 80 measured by Doppler ultrasound strongly predicts deteriorating renal function in type 2 diabetic patients with microalbuminuria.
Absolute Event Rate: 24% vs 5%
p-value: p=<0.01
Type 2 diabetic patients often die because of end-stage renal failure, but no definitive reliable factor predicting long-term renal outcome has been identified. We tested whether a renal arterial resistance index (R/I) > or =80, using Doppler ultrasound technique, was predictive of worsening renal function. The primary end points of the study were 1) the course of glomerular filtration rate (GFR) and 2) the albumin excretion rate in 157 microalbuminuric, hypertensive, type 2 diabetic patients after a 7.8-year follow-up period (range 7.1-9.2). Kaplan-Meier curves for the primary end point (decrease of GFR > or = -3.0 ml/min per 1.73 m(2) per year) was two to three times more frequently observed in patients with R/I > or =80. Four- to fivefold fewer patients showed a regression to normoalbuminuria during the follow-up period from baseline microalbuminuria in the cohort with R/I > or =80. Overt proteinuria did develop in 24% of patients with R/I > or =80 and in 5% of patients with R/I <80 (P < 0.01). In conclusion, intrarenal arterial resistance appears to play a nontrivial role in deteriorating renal function in type 2 diabetic patients. R/I is a noninvasive diagnostic procedure, which strongly predicts the outcome of renal function in type 2 diabetic patients, even when GFR patterns are still normal.
Nosadini et al. (2006) conducted a cohort in Type 2 diabetes with microalbuminuria (n=157). Renal arterial resistance index (R/I) ≥80 vs. Renal arterial resistance index (R/I) <80 was evaluated on Course of glomerular filtration rate (GFR) and albumin excretion rate (development of overt proteinuria) (p=<0.01). A renal arterial resistance index ≥80 predicted worsening renal function, with overt proteinuria developing in 24% of patients with an index ≥80 compared to 5% with an index <80 (P<0.01).