A review article: sevelamer hydrochloride and metabolic acidosis in dialysis patients

Sevelamer hydrochloride is a phosphate binder and its effectiveness to reduce the cardiovascular mortality of dialysis patients has been tested. Sevelamer hydrochloride also contains chlorine, so a decrease in bicarbonate due to chlorine load was anticipated and metabolic acidosis thought to associate with sevelamer hydrochloride has been reported in some papers. We reported that sevelamer hydrochloride exacerbated metabolic acidosis in hemodialysis patients, depending on the dosage. Also a Japanese nationwide survey suggested that sevelamer hydrochloride usage potentially aggravates acidosis in dialysis patients. A multi-institute research study by Edmung et al. has shown that metabolic acidosis, with serum CO2 below 17.5 mmol/L, is by itself associated with increased risk of death in dialysis patients. Furthermore, the Dialysis Outcomes and Practice Patterns Study (DOPPS) revealed that both high (> 27 mmol/L) and low (< or = 17 mmol/L) serum bicarbonate (total CO2) levels were associated with increased risk for mortality and hospitalization. There has not been any significant evidence to show that sevelamer hydrochloride has reduced the cardiovascular mortality of dialysis patients compared with calcium-based binder. Clinicians should check not only the level of chlorine but also the level of total CO2 or bicarbonate during the treatment with sevelamer hydrochloride, and control metabolic acidosis.