Skeletal and cardiovascular consequences of a positive calcium balance during hemodialysis

Abstract

Patients on hemodialysis are exposed to calcium via the dialysate at least three times a week. Changes in serum calcium vary according to calcium mass transfer during dialysis, which is dependent on the gradient between serum and dialysate calcium concentration (d[Ca]) and the skeleton turnover status that alters the ability of bone to incorporate calcium. Although underappreciated, the d[Ca] can potentially cause positive calcium balance that leads to systemic organ damage, including associations with mortality, myocardial dysfunction, hemodynamic tolerability, vascular calcification, and arrhythmias. The pathophysiology of these adverse effects includes serum calcium changes, parathyroid hormone suppression, and vascular calcification through indirect and direct effects. Some organs are more susceptible to alterations in calcium homeostasis. In this review, we discuss the existing data and potential mechanisms linking the d[Ca] to calcium balance with consequent dysfunction of the skeleton, myocardium, and arteries.

A feasibility study of avoiding positive calcium balance and parathyroid hormone increase in patients on peritoneal dialysis

“…Data from the Dialysis Practice Patterns and Results Study (DOPPS) show there is still a considerable percentage of patients on PD receiving dialysis with d[Ca] of 1.75 mmol/L ( Wang et al, 2019 ), which is also true for Brazil ( Weissheimer et al, 2021 ), despite the recommendation of a d[Ca] between 1.25 and 1.50 mmol/L ( Uhlig et al, 2010 ; C.K.D.M.B.D.W.G, 2009 ). Knowing the risks of a positive calcium balance for patients with advanced CKD ( Elias et al, 2021 ), the results from our study should encourage a spread use of recommended d[Ca] from 1.25 to 1.5 mEq/L.…”