The role of magnesium binders in chronic kidney disease.

Magnesium is predominantly an intracellular cation that plays a critical role in cellular physiology. Serum levels are often slightly elevated in patients on chronic hemodialysis and older reports suggests that total body stores may also be increased, based on bone biopsies in patients treated with higher dialysate magnesium levels than are currently in use today. Several studies have shown that magnesium, particularly in the form of magnesium carbonate, is an effective phosphate binder and can decrease patients' exposure to calcium. Retrospective studies suggest that magnesium may prevent vascular calcification in dialysis patients, although this remains controversial and has not been evaluated prospectively. Magnesium may reduce arrhythmias postoperatively and, while it may theoretically reduce arrhythmic death in dialysis patients, this hypothesis has never been tested. While short-term or adjuvant use of magnesium carbonate appears safe and effective as a phosphate binder, more studies are needed to evaluate the long-term effects on vascular calcification, bone histology, and mortality.