Kidney Week

Abstract: FR-OR110

Effects of 3.0 mEq/L [K+] Dialysate with Sodium Zirconium Cyclosilicate (SZC) vs. 2.0 mEq/L [K+] Dialysate without SZC on Cardiac Arrhythmia Rates

Session Information

• Late-Breaking Science Orals - 1
  October 25, 2024 | Location: Room 6C, Convention Center
  Abstract Time: 05:10 PM - 05:20 PM

Category: Dialysis

• 801 Dialysis: Hemodialysis and Frequent Dialysis

Authors

• Winkelmayer, Wolfgang C., Baylor College of Medicine, Houston, Texas, United States

Wolfgang C. Winkelmayer, MD, ScD, MPH, FASN

• Charytan, David M., New York University Grossman School of Medicine, New York, New York, United States

David M. Charytan, MD, MS, MSc

• Granger, Christopher B., Duke University Duke Clinical Research Institute, Durham, North Carolina, United States

Christopher B. Granger, MD

• Middleton, John Paul, Duke University Medical Center, Durham, North Carolina, United States

John Paul Middleton, MD

• Herzog, Charles A., Hennepin Healthcare System Inc, Minneapolis, Minnesota, United States

Charles A. Herzog, MD

• Chertow, Glenn M., Stanford University School of Medicine, Stanford, California, United States

Glenn M. Chertow, MD, MPH, FASN

• Eudicone, James M., AstraZeneca Pharmaceuticals LP, Wilmington, Delaware, United States

James M. Eudicone, MS, MBA

• Tumlin, James A., NephroNet, Inc., Atlanta, Georgia, United States

James A. Tumlin, MD, FASN

Group or Team Name

• ADAPT Investigators.

Background

K⁺ homeostasis may be a modifiable risk factor for atrial fibrillation (AF) and clinically significant cardiac arrhythmias (CSCA) in patients receiving hemodialysis (HD). The optimal approach to managing serum K⁺ (sK⁺) and dialysate K⁺ (dK⁺) is uncertain.

Methods

ADAPT was a prospective, randomized, open-label 2×2 crossover trial. Adults receiving HD 3 d/wk for ≥3 mo with hyperkalemia (two predialysis sK⁺ measurements 5.1–6.5 mEq/L) underwent placement of an implantable cardiac loop recorder and were randomized 1:1 to one of two crossover sequences: A) 2.0K⁺/2.5Ca²⁺ mEq/L dialysate bath without SZC (2.0K⁺/noSZC) for 8 wks followed by 3.0K⁺/2.5Ca²⁺ mEq/L dialysate bath with SZC on non-HD days (3.0K⁺/SZC) for 8 wks, or B) vice versa. SZC starting dose (on non-HD days) was 5 g, up titrated weekly to 15 g to maintain predialysis sK⁺ 4.0–5.5 mEq/L. sK+ was measured pre-HD and <30 min prior to rinse back once weekly. The primary outcome was the rate of AF episodes >2 min duration. Key secondary outcomes included rate of CSCA and proportion of sK⁺ values within an ‘ideal’ window of 4.0-5.5 mEq/L.

Results

Overall, 88 pts (mean age 57.1 yrs, 51.1% male, mean sK⁺ 5.5 mmol/L) were randomized. Over 25.5 person yrs (PY), 296 AF episodes were recorded among 9 (10.2%) patients. The crude AF rate was lower with 3.0K⁺/SZC (9.7/PY) vs 2.0K⁺/noSZC (13.4/PY); modelled rate ratio (RR): 0.52; 95% CI 0.41; 0.65; P<0 001. The rate of CSCA was lower with 3.0K⁺/SZC (6.8/PY) than 2.0K⁺/noSZC (10.2/PY); RR: 0.47; 95% CI 0.38; 0.58; P<0.001. The mean proportion of monitoring time spent in AF (0.22% vs 0.53%; RD: -0.30%; 95% CI -1.11%; 0.45%) did not differ significantly between exposure groups. Pts with 3.0K⁺/SZC had lower odds of sK+ being outside the ideal window; OR: 0.27; 95% CI 0.12; 0.35. Hypokalemia occurred in 33 pts with 3.0K⁺/SZC vs 58 patients with 2.0K⁺/noSZC. Hyperkalemia occurred in 3 pts with 3.0K⁺/SZC vs 1 pt with 2.0K⁺/noSZC. Adverse events occurred in 37 vs 28 pts with 3.0K⁺/SZC vs 2.0K⁺/noSZC.

Conclusion

Among patients receiving maintenance HD with a history of hyperkalemia, a combination of dK⁺ 3.0 mEq/L and SZC on non-HD days reduced the rates of AF, CSCA, and post-HD hypokalemia compared with dK⁺ 2.0 mEq/L and no SZC.

Funding

• Commercial Support – AstraZeneca