Time-varying serum albumin levels and all-cause mortality in prevalent peritoneal dialysis patients: a 5-year observational study.

BACKGROUND: In this study, we investigated the association of time-varying serum albumin levels with mortality over a 5-year period in one cohort of patients undergoing long-term peritoneal dialysis (PD) therapy. METHODS: The participants in this study enrolled 302 patients who underwent long-term PD at a single PD center in Taiwan. We reviewed medical records from 2011 to 2015 retrospectively. Time-averaged albumin level and serum albumin reach rate (defined as the percentage of serum albumin measurements that reached ≥3.5 g/dL) were applied as the predictor variables in the first 2 years (2011-2012). All-cause mortality was used as the outcome variable in the subsequent 3 years (2013-2015). Hazard function of all-cause mortality in the study participants was examined by using Cox proportional hazard regression models . RESULTS: Patients with different albumin reach rates (75-< 100%, 50-< 75%, 1-< 50%) did not exhibit a significantly increased risk for all-cause mortality. Patients with a 0% albumin reach rate exhibited a significantly increased risk for all-cause mortality (hazard ratio [HR] 7.59, 95% confidence interval [CI], 2.38-24.21) by fully adjusted analysis. Patients with time-averaged albumin levels of < 3.5 g/dL (HR 15.49, 95% CI 1.74-137.72) exhibited a higher risk for all-cause mortality than those with serum albumin levels ≥4.0 g/dL. CONCLUSIONS: This study demonstrated that higher serum albumin reach rates and higher time-averaged serum albumin levels are associated with a lower mortality rate over a 5-year period among patients undergoing long-term PD.

Longitudinal Changes of PAI-1, MMP-2, and VEGF in Peritoneal Effluents and Their Associations with Peritoneal Small-Solute Transfer Rate in New Peritoneal Dialysis Patients.

Patients on peritoneal dialysis (PD) encounter peritoneal functional and structural alterations. It is still unknown whether levels of plasminogen activator inhibitor type 1 (PAI-1), matrix metalloproteinases- (MMP-) 2, and vascular endothelial growth factor (VEGF) exhibit dynamic changes in peritoneal effluents. The aim of the present study was to investigate the longitudinal changes in these biomarkers in PD patients and their association with peritoneal small-solute transfer rate (PSTR). This prospective, single-center cohort study included 70 new PD patients. The presence of PAI-1, MMP-2, and VEGF in peritoneal effluents was measured regularly after PD initiation. The association between those biomarkers and 4-hour effluent:plasma creatinine ratio (PSTR) was analyzed. Longitudinal follow-up showed a tendency for PAI-1 (p < 0.001) and VEGF (p = 0.04) to increase with the duration of PD. Both PSTR at baseline and PSTR at 2 years significantly associated with PAI-1, MMP-2, and VEGF levels at baseline. PSTR at 2 years also associated with the MMP-2 level at 6 months and PAI-1 level at baseline. The present study illustrated a positive association of PSTR with selected biomarkers in peritoneal effluents observed over a 2-year period.

Adherence to phosphate binder therapy is the primary determinant of hyperphosphatemia incidence in patients receiving peritoneal dialysis.

We investigated the major determinant of hyperphosphatemia incidence among patients receiving peritoneal dialysis. Seventy-six patients aged 25-55 years who had received peritoneal dialysis for more than 3 months were recruited. The patients were divided into three groups according to their serum phosphorus levels (Group 1, ≥ 6 mg/dL; Group 2, 5.9-4.8 mg/dL; and Group 3, <4.8 mg/dL). Renal dietitians interviewed the patients to determine their phosphate intake and adherence to phosphate binder therapy. No statistical differences in demographics or phosphate intake were identified among the groups. However, adherence to phosphate binders was greater in Group 3 than in Groups 1 and 2 (96.3% vs. 21.4% and 52.4%, respectively; P < 0.001). Multivariate analysis showed that adherence to phosphate binder therapy was the only significant contributor to serum phosphorus levels (P= 0.0001). Adherence to diet was better than adherence to phosphate binder therapy among patients receiving peritoneal dialysis, and the latter determined the incidence of hyperphosphatemia.