Comparative analysis of hypertension and its causes among renal replacement therapy patients

In renal replacement therapy (RRT) patients, the target values of blood pressure (BP) are being continuously modified and excessive fat tissue may even have a protective impact on the risk of mortality due to cardiovascular causes - the "obesity paradox". The purpose of the study was to compare the occurrence of hypertension (HTN) and its underlying causes in patients in the first year after kidney transplantation (KTx), and hemodialysis (HD) or peritoneal dialysis (PD) patients.

A group of 120 RRT patients (PD, n=30; HD, n=40; KTx, n=50) was analyzed. The following research tools were used: (1) 24- or 44-h ambulatory blood pressure monitoring (ABPM); (2) bioelectrical impedance analysis (BIA); (3) traditional method - office BP; (4) Morisky-Green test; and (5) disease history. The significance level was p<0.05.

The analysis revealed (HTN) (on the basis of ABPM values and anti-hypertensive treatment) in 90% of PD patients, 83% of HD patients in the first 24 h after hemodialysis, and in 95% of HD patients in the second 24 h after hemodialysis. In patients in the 12(th) month after KTx, BP values went up along with increased creatinine and hemoglobin concentration and urine protein presence (r=0.38; r=0.31; r=0.38; p<0.05). HD had a statistically significant impact of fat tissue growth on reducing BP (r=-0.34; p<0.05).

Fat tissues play a cardioprotective role in the development of hypertension in HD patients. This shows the possibility of early noninvasive identification of patients exposed to development of chronic allograft nephropathy.