Managing dry weight and hypertension in dialysis patients: still a challenge for the nephrologist in 2009?

Hypertension prevalence is high in both hemodialysis and peritoneal dialysis patients. Among several possible mechanisms leading to hypertension in chronic kidney disease, the most important is the positive balance of sodium and accumulation of extracellular fluid causing cardiovascular remodeling. Hypertension may provoke de novo left ventricular hypertrophy and cardiac failure in dialysis patients and is also associated with a higher risk of stroke. The relationship between hypertension and mortality is unexpected, with better survival in hypertensive patients in short-term studies in which heart failure associated with low blood pressure and high death rate confounds the effect of hypertension on death risk. Higher mortality is found in hypertensive patients surviving beyond 2 years under dialysis treatment. The non pharmacological treatment of hypertension - the dry weight method - is efficient to correct hypertension when applied. A recent randomized controlled trial has confirmed its efficiency in lowering blood pressure. A low-salt diet is part of this strategy limiting the interdialytic weight gain and enhancing tolerance to ultrafiltration. Moreover, according to recent meta-analyses, the prescription of antihypertensive medications is associated with better survival. Their appropriate use remains to be studied. In conclusion, the important challenge for the nephrologist in 2009 is to efficiently correct extracellular fluid overload and its consequences, with the goal of improving the high burden of cardiovascular mortality among dialysis patients.