[Does hypertension impact on the mortality of hemodialysis patients?].

Hypertension is very common in standard haemodialysis patients in spite of a wide use of antihypertensive medications. Up to the last decade it was reported in dialysis nts, as in the general population, as a powerful mortality risk factor. More recently several reports have challenged this view, and hypotension rather than hypertension has been claimed as the real culprit. That a risk factor has an opposite effect on mortality in conditions such as dialysis than in the general population has been termed - reverse epidemiology ,,, and suggests that our therapeutic approach toward blood pressure control in dialysis should be reconsidered. In fact, this counter intuitive concept is explained by the effect of time. Hypertension is a long-term mortality risk factor, that in a population crippled by short-acting risk factors (e.g. diabetes, congestive heart failure, malnutrition...) has not the opportunity to express itself. The clear cut noxious effect of hypertension on mortality in the years when dialysis patients were young and fit has disappeared in the present aged and highly co-morbid population. This does not mean that hypertension becomes beneficial once dialysis has been started. Hypotension is a marker of a high risk of early mortality, hypertension is a cause of late mortality. There is no evidence that hypertension might be protective in dialysis patients. Avoiding hypertension remains a capital goal of maintenance dialysis.