Arterial hypertension in dialysis: up to what point should it be corrected? A lot!

Arterial hypertension is a powerful predictor of cardiovascular events and mortality in the general population. It is well known that the prevalence of hypertension is high in hemodialysis patients, but there is still debate on the existence of a cause-effect relationship between high blood pressure and mortality in patients with end-stage renal disease. Although some authors have suggested a positive association between low blood pressure values and mortality, various studies have shown that blood pressure reduction improves survival and reduces cardiovascular events in hemodialysis patients. Furthermore, a close relationship between blood pressure and mortality has been revealed recently by data obtained from ambulatory and home blood pressure monitoring, whereas blood pressure values recorded in dialysis units seem to have poor prognostic value. Even though a hemodialysis session generally induces a reduction in blood pressure, in part of the patients a rise in blood pressure may be observed. This phenomenon, known as intradialytic hypertension, is associated with a worse prognosis in terms of mortality and with an increased incidence of hospitalization. As the extracellular fluid level is the main factor influencing blood pressure values in hemodialysis patients, correct determination of dry weight is of fundamental importance in order to obtain blood volume and pressure control in this population. Regarding antihypertensive drug therapy, the few trials that are currently available have shown that angiotensin-II inhibitors and dihydropyridine calcium channel blockers exert a protective cardiovascular effect. In conclusion, high blood pressure levels in hemodialysis patients are associated with an increased risk of death and cardiovascular events. Reduction of blood pressure in these patients improves survival and reduces adverse events just like in hypertensive patients without end-stage renal disease. It is possible, however, that patients who have more comorbidities may not tolerate, especially during hemodialysis sessions, certain blood pressure levels that are known to be preferable in subjects that are less compromised.