Abstract: PO0894
Metabolic Alkalosis in Hemodialysis Patients: Worse Outcomes?
Session Information
- Fluid, Electrolytes, and Clinical Events with Dialysis: Getting to the "Heart" of the Matter
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Dialysis
- 701 Dialysis: Hemodialysis and Frequent Dialysis
Authors
- Ávila, Gonçalo, Dialverca-dialysis clinic, Forte da Casa, Portugal
- Matias, Patrícia, Dialverca-dialysis clinic, Forte da Casa, Portugal
- Laranjinha, Ivo Jos? Dias, Dialverca-dialysis clinic, Forte da Casa, Portugal
- Gil, Célia, Dialverca-dialysis clinic, Forte da Casa, Portugal
- Ferreira, Manuel A., Dialverca-dialysis clinic, Forte da Casa, Portugal
Background
The ideal serum bicarbonate levels in prevalent hemodialysis (HD) patients is still debatable. Metabolic alkalosis in these patients has been associated with increased morbimortality. The aim of this study was to evaluate the association between serum bicarbonate and nutritional and cardiovascular risk markers, hospitalizations and mortality.
Methods
This was a single-center, retrospective study, of a cohort of 158 in-center HD patients, with a duration of 24 months. Serum bicarbonate levels were evaluated predialysis every 3 months. Body Composition Monitor was used to assess nutritional and hydration status. Electrocardiogram and echocardiogram data were obtained to calculate the QTc interval and the left ventricular mass index, respectively. Vascular calcifications were assessed using the Adragão score (SVCS).
Results
Mean age of the population was 69.8±12.6, 73% were male and 45% had diabetes. Median HD vintage was 59 months (IQR: 65 months). Mean serum bicarbonate was 23,5±1,57 mEq/L. There was as inverse association between serum bicarbonate and body mass index (r=-0.22, p=0.006), lean tissue index (r=-0.35, p<0.001), hemoglobin (r=-0.19, p=0.016), albumin (r=-0.30, p<0.001), phosphorus (r=-0.33, p<0.001) and nPCR (r=-0.41, p<0.001). Patients with greater SCVS (≥3) had higher mean serum bicarbonate (24.1±1.29 vs. 22.4±1.36 mEq/L, p<0.001). Higher serum bicarbonate was associated with an increased number of infection-related hospitalizations (p=0.009) and mortality (p=0.024), as well as all-cause mortality (p=0.012). Kaplan-Meier analysis revealed a significantly higher all-cause mortality in patients with serum bicarbonate ≥ 24.5 mEq/L at 24 months. The Cox regression analysis showed that serum bicarbonate was a predictor of all-cause mortality (p=0.004) in a model adjusted for age, dialysis vintage and the presence of diabetes.
Conclusion
In this population, higher serum bicarbonate was associated with a worse nutritional status and a higher cardiovascular risk, assessed by Adragão score. There was an association with an increased number of infection-related hospitalizations and mortality, as well as higher all-cause mortality. Serum bicarbonate levels ≥24.5 mEq/L were associated with lower survival at 24 months. Prospective studies are needed to determine the ideal serum bicarbonate levels in HD patients.