Vascular calcification and cardiac function according to residual renal function in patients on hemodialysis with urination

BACKGROUND: Vascular calcification is common and may affect cardiac function in patients with end-stage renal disease (ESRD). However, little is known about the effect of residual renal function on vascular calcification and cardiac function in patients on hemodialysis. METHODS: This study was conducted between January 2014 and January 2017. One hundred six patients with residual renal function on maintenance hemodialysis for 3 months were recruited. We used residual renal urea clearance (KRU) to measure residual renal function. First, abdominal aortic calcification score (AACS) and brachial-ankle pulse wave velocity (baPWV) were measured in patients on hemodialysis. Second, we performed echocardiography and investigated new cardiovascular events after study enrollment. RESULTS: The median KRU was 0.9 (0.3–2.5) mL/min/1.73m(2). AACS (4.0 [1.0–10.0] vs. 3.0 [0.0–8.0], p = 0.05) and baPWV (1836.1 ± 250.4 vs. 1676.8 ± 311.0 cm/s, p = 0.01) were significantly higher in patients with a KRU < 0.9 mL/min/1.73m(2) than a KRU ≥ 0.9 mL/min/1.73m(2). Log-KRU significantly negatively correlated with log-AACS (ß = -0.29, p = 0.002) and baPWV (ß = -0.19, P = 0.05) after factor adjustment. The proportion of left ventricular diastolic dysfunction was significantly higher in patients with a KRU < 0.9 mL/min/1.73m(2) than with a KRU ≥ 0.9 mL/min/1.73m(2) (67.9% vs. 49.1%, p = 0.05). Patients with a KRU < 0.9 mL/min/1.73m(2) showed a higher tendency of cumulative cardiovascular events compared to those with a KRU ≥ 0.9 ml/min/1.73m(2) (P = 0.08). CONCLUSIONS: Residual renal function was significantly associated with vascular calcification and left ventricular diastolic dysfunction in patients on hemodialysis.