Dietary sodium restriction for hypertension in dialysis patients.

A close relationship between sodium and hypertension exists and this relationship is even more pronounced in renal failure and dialysis patients. Hypertension is one of the strongest predictors of poor outcome in dialysis patients. Almost all end-stage renal disease (ESRD) patients have hypertension and positive sodium balance, resulting in extracellular volume (ECV) expansion-the most important contributing factor to hypertension. Thus the effective management of hypertension requires normalization of the sodium balance and ECV. Two important methods to achieve this are limiting interdialytic weight gain (IDWG) and a dialysis process that is able to remove all IDWG and consistently attain dry weight. Since IDWG is directly dependent on sodium intake and the resulting thirst, sodium restriction is the most effective way to limit IDWG. Ultrafiltration and dialysate sodium concentration influence sodium removal, ECV control, and blood pressure (BP) control. Thus the dialysis session should be long enough to achieve dry weight and frequent enough to maintain appropriate BP.