Abstract: Objective To investigate the association of serum uric acid (SUA) level with dialysis adequacy and nutritional status in peritoneal dialysis (PD) patients. Methods This was a retrospective study involving 266 subjects who started PD in our center from January 2008 to July 2014 and were followed up for more than 12 months. Patients were divided into hyperuricemia group and normal SUA group based on SUA level. The association of SUA with nutritional status including prealbumin, total protein, albumin, normalized protein catabolic rate, blood urea nitrogen and with PD adequacy indices including Kt/V, total creatinine clearance
(Ccr) and residual renal function (RRF) were analyzed. Results As compared with normal SUA group at baseline, patients in hyperuricemia group at baseline had higher prealbumin (367.076±75.734 vs. 344.644± 72.750 mg/L, t=2.428, P=0.016), total protein (62.713±8.223 vs. 59.807±6.916 g/L, t=3.058, P=0.002), albumin (33.671 ± 4.307 vs. 31.025 ± 4.812 g/L, t=4.678, P＜0.001), serum creatinine (728.096 ± 271.527 vs.647.550 ± 242.555 μmol/L, t=2.525, P=0.012), blood urea nitrogen [18.000 (14.300, 22.450) vs. 14.850 (12.150, 18.200) mmol/L, Z=- 4.205, P＜0.001], triglyceride [1.805 (1.285, 2.537) vs. 1.475 (1.129, 2.382) mmol/L, Z=- 2.241, P=0.025] and phosphorus [1.545 (1.288, 1.803) vs. 1.335 (1.130, 1.530) mmol/L, Z=- 4.519, P＜0.001]. After PD for 12 months, SUA decreased obviously (410.335±86.769 vs. 387.966±79.638 μmol/L, t=4.640, P＜0.001). Multiple regression analyses showed that SUA was positively correlated with male gender (β=28.473, P=0.011), body mass index (β=3.903, P=0.015), systolic blood pressure (β=0.882, P= 0.010), albumin level (β=3.205, P=0.013), and phosphorus level (β=42.248, P=0.005), and negatively correlated with age (β=-0.966, P=0.011), history of diabetes mellitus (β=-25.427, P=0.047), and Kt/V (β=-21.214, P= 0.019). Logistic regression analyses indicated that male, history of diabetes, hyperuricemia, higher body mass index, lower hemoglobin, and lower RRF were significantly correlated with inadequate dialysis. Conclusions PD can effectively improve hyperuricemia. SUA level was closely correlated with nutritional status and dialysis adequacy. Higher SUA in PD patients may suggest the relatively good nutritional status, but hyperuricemia may also associate with inadequate dialysis.

Key words: peritoneal dialysis, serum uric acid, dialysis adequacy, nutritional status