Variations in Serum Albumin Levels Over Time in Patients Treated With Conventional Hemodialysis or Expanded Hemodialysis: A Cohort Study.

Abstract

Introduction: Hypoalbuminemia is a well-established risk factor for mortality in chronic hemodialysis (HD) patients. To evaluate the association of time-varying serum albumin with the type of dialyzer, we analyzed serum albumin over time in two cohorts of HD patients, one receiving HDx therapy enabled by the Theranova dialyzer and the other conventional HD with high-flux dialyzer (HF-HD).

Methods: In this cohort study, 1092 prevalent adult HD patients (mean age 61 years; 62% men; 42% had diabetes; 19% had cardiovascular disease) at Renal Care Services Colombia undergoing either HDx therapy enabled by Theranova dialyzer (n = 559) or HF-HD (n = 533) were enrolled between September 1, 2017, and November 30, 2017, and then underwent repeated measurements of serum albumin for up to 48 months. Sociodemographic and clinical, and laboratory characteristics at baseline were recorded, and a repeated-measures analysis of variance (ANOVA) was conducted to examine differences in means of serum albumin at different time points. To evaluate the association between dialysis membrane and albumin levels during the follow-up, a linear panel regression analysis was performed, allowing control for imbalances in the cohorts of baseline clinical and demographic variables, as well as the time-dependent variables.

Results: Mean albumin concentration remained above 3.8 g/dL and did not differ over time between HDx and HF-HD (p = 0.789). No association (p = 0.208) between serum albumin levels varying over time and the use of the Theranova dialyzer was found in the linear panel regression model. However, serum albumin was linked to both inflammatory and nutritional markers, including C-reactive protein, ratio of platelets to lymphocytes, and protein-energy wasting.

Conclusion: Variations in serum albumin levels over time were associated with protein-energy wasting, inflammation, high age, vascular access, and hospitalizations, but not with the type of dialyzer.