Effect of the interaction between estimated glomerular filtration rate and serum uric acid on all-cause and cardiovascular mortality in patients on peritoneal dialysis / 中华肾脏病杂志

ABSTRACT

Objective:To explore the effect of the interaction between estimated glomerular filtration rate (eGFR) and serum uric acid (SUA) on all-cause and cardiovascular mortality in patients on peritoneal dialysis (PD).Methods:Patients who performed PD catheterization at the PD center of the First Affiliated Hospital of Sun Yat-sen University and had initiated PD therapy for over 3 months from January 2006 to December 2016 were enrolled and followed up until December 2018. Demographic data, baseline clinical and laboratory examination results of the patients were collected. Kaplan-Meier survival curve and Cox regression analysis were used to explore the correlation between SUA and all-cause mortality, cardiovascular mortality in different eGFR groups of PD patients.Results:A total of 2 124 PD patients were enrolled with age of (47.0±15.2) years, among whom 1 269 patients were male and 536 patients had diabetes. The SUA level was (429±96) μmol/L and the median level of eGFR was 6.69(5.17, 8.61) ml·min -1·(1.73 m 2) -1. After a median follow-up time of 42 months, 554 patients died, among whom 275 patients were cardiovascular death. The Cox regression analysis revealed that there was a significant interaction between eGFR and SUA on all-cause mortality ( P=0.043). The Kaplan-Meier curve showed that the tertile 1 (SUA<384 μmol/L) and tertile 3 (SUA>460 μmol/L) group had significantly higher all-cause mortality ( P=0.009) than the reference group of tertile 2 (SUA 384-460 μmol/L) in the higher eGFR group [eGFR>6.69 ml·min -1·(1.73 m 2) -1]but not in the lower eGFR. After adjusting for relevant demographic data, complications, biochemical results and other variables, in patients with higher eGFR, the risk of all-cause mortality increased by 0.2% ( HR=1.002, 95% CI 1.000-1.003, P=0.019) for every 1 μmol/L increase in SUA. In addition, compared with the tertile 2 reference group, the tertile 3 group was independently correlated with higher risk of all-cause mortality ( HR=1.670, 95% CI 1.242-2.245, P=0.001). Conclusions:The eGFR and SUA level significantly interacts with all-cause mortality, and the higher SUA level in higher eGFR group is an independent risk factor for all-cause mortality in PD patients.