Abstract: TH-PO142
Effect of Dialysate Bicarbonate on Calciprotein Crystallization Time (T50) in Hemodialysis Patients: The D-Bic Study
Session Information
- CKD-MBD: Clinical
October 24, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bone and Mineral Metabolism
- 502 Bone and Mineral Metabolism: Clinical
Authors
- Cejka, Daniel, Ordensklinikum Linz GmbH Elisabethinen, Linz, Oberösterreich, Austria
- Neufeld, Peter Stefan, Ordensklinikum Linz GmbH Elisabethinen, Linz, Oberösterreich, Austria
- Pasch, Andreas, Calciscon AG, Biel, Switzerland
- Smith, Edward R., Royal Melbourne Hospital, Parkville, Department of Nephrology Victoria, Australia, Melbourne, Victoria, Australia
- Gaggl, Martina M., Center for Public Health, Public Health Nutrition, Medical University Vienna, Vienna, Austria
- Haller, Maria C., Ordensklinikum Linz GmbH Elisabethinen, Linz, Oberösterreich, Austria
- Machacek, Jennifer Daniela, Ordensklinikum Linz GmbH Elisabethinen, Linz, Oberösterreich, Austria
Background
Short calciprotein crystallization time (low T50) is directly associated with increased risk of cardiovascular events and mortality. Higher serum bicarbonate levels consistently correlate with higher T50 time in observational studies. However, oral supplementation of sodium bicarbonate failed to increase T50 times in interventional studies in CKD patients. Here, we investigated whether increases in dialysate bicarbonate concentrations increase T50 times.
Methods
In a prospective, single center, single arm, interventional trial, dialysate bicarbonate was decreased from baseline settings to 27 mmol/l (D-Bic 27) in a step-wise fashion (2 mmol/l change per dialysis session), followed by a step-wise increase in dialysate bicarbonate settings to 37 mmol/l (D-Bic 37), over a course of 6 weeks. The primary endpoint was the change in T50 time between the D-Bic 27 and D-Bic 37 phase.
Results
Of 29 recruited patients, 24 completed the study per protocol. T50 time increased significantly from 246 ± 77 to 282 ± 81 minutes from the D-Bic 27 to the D-Bic 37 phase (p<0.0001). The hydrodynamic radius (size) of secondary calciprotein particles generated in the T50 test (CPP-2Rh) did not differ significantly between the D-Bic 27 and D-Bic 37 phase (251± 75 vs. 240 ± 78 nm, p=0.27). Serum bicarbonate, serum pH, and intact parathyroid hormone (PTH) increased significantly, while ionized serum calcium decreased significantly from the D-Bic 27 to the D-Bic 37 phase. Serum potassium, phosphate and magnesium did not change significantly throughout the study.
Conclusion
Increases in dialysate bicarbonate led to significant increases in T50 time.