Association of increased arterial wave reflections with decline in renal function in chronic kidney disease stages 3 and 4

Increased arterial wave reflections predict cardiovascular events in dialysis patients. Their impact on the progression of renal disease has not been determined.

We prospectively quantified wave reflections as pressure augmentation (AP) and augmentation index (AIx) using radial applanation tonometry and a transfer function, in 111 patients (mean age 53.6 years; 71 men, 31 diabetics) with chronic kidney disease not requiring dialysis. Primary endpoint was a composite of doubling of serum creatinine, need for dialysis, and transplantation. Secondary endpoint was a combination of renal and cardiovascular events.

After a mean follow-up of 41.3 months, 37 and 46 patients reached the primary and the secondary endpoint. AIx and AP proved statistically significant predictors of the renal endpoint (P < 0.05 for all), with a 2.5- and 3-fold increased risk for patients in the highest vs. the lowest tertile, respectively. After adjustment for mean blood pressure (MBP), age, gender, diabetes, serum albumin, hemoglobin, urine albumin/creatinine ratio, and renal function at baseline, AIx (hazard ratio 1.474/10% increase in AIx, P = 0.04) as well as AP (hazard ratio 1.559/10 mm Hg increase in AP, P = 0.04) remained significant predictors of the renal endpoint. In addition, AIx and AP were significant (P < 0.05) predictors of the combined cardiorenal endpoint in univariate analysis and multivariable models.

Increased arterial wave reflections are independent predictors of renal as well as cardiorenal events in patients with chronic kidney disease.