Association Between Hypertension and Residual Renal Function in Hemodialysis Patients

Introduction. Cardiovascular diseases are the leading cause of death in hemodialysis patients. The decline of residual renal function increases the prevalence and severity of risk factors of cardiovascular morbidity and mortality in these patients. Hypertension is common in dialysis patients and represents an important independent factor of survival in these patients. Methods. The study included 77 patients who are on chronic HD for longer than 3 months. Depending on the measured residual diuresis patients were divided into two groups. The study group consisted of patients with residual diuresis >250 ml/day, while patients from control group had residual diuresis <250 ml/day. All patients had their blood pressure measured before 10 consecutive hemodialysis treatments. Collected data were statistically analyzed using SPSS 16.0. Results. The study included 77 hemodialysis patients, mean age of 56.56±14.6 years and mean duration of hemodialysis treatment of 24.0 months. Of the total number of patients, 39(50.6%) had preserved residual renal function. Hypertension was more common in the group of patients who did not have preserved residual renal function (68.4% vs 25.6%). There was statistically significant negative linear correlation between the volume of residual urine output and the residual clearance of urea and values of systolic blood pressure [(rho=-0.388; p<0.0001); (rho=0.392; p<0.0005)], values of mean arterial pressure [(rho =-0.272; p<0.05); (rho=-0.261; p=0.023; p<0.05)] and values of pulse pressure in hemodialysis patients [(rho =-0.387; p<0.001); (rho=-0.400; p<0.0005)]. Conclusions. Residual renal function plays an important role in controlling blood pressure in patients on hemodialysis. More attention should be directed to preserve residual renal function, and after the start of hemodialysis by avoiding intensive ultrafiltration with optimal antihypertensive therapy.