Management of hyperphosphatemia

Abstract

Hyperphosphatemia is a well recognized risk factor for cardiovascular mortality in dialysis patients. Despite advanced technology and regular and efficient dialysis treatment the prevalence of hyperphosphatemia is still high. The goal of normalization of serum phosphorus (iP) levels can only be reached by optimization of dialysis prescription in combination with individualized dietary and medical strategies. Due to the unique characteristics of intradialytic iP kinetics, dialysis treatment time and frequency are the most effective factors governing intradialytic iP removal. Although the combination of diffusive and convective removal by hemodiafiltration allows a further increase in iP mass removal, a neutral phosphorus balance without dietary restrictions and the use of phosphate binders has only be achieved by daily nocturnal hemodialysis. Strict dietary phosphate restriction bears the risk of inadequate protein intake and the development of protein/calorie malnutrition. Although phosphate binders (PB) can effectively lower serum iP levels into the normal range, this is rarely achieved in clinical practice probably due to inadequate relation of PB dose to dietary phosphorus intake. Developing methods to enable patients to self-adjust phosphate binder dose to individual meal phosphate content, similar to adjusting insulin dose to carbohydrate intake, may lead to further improvements in phosphate management.