Effect of long-term losartan administration on renal haemodynamics and function in hypertensive patients

In this study the efficacy and safety of long-term losartan administration on renal haemodynamics were evaluated in mild to moderate hypertension. Aft er a run-in period with placebo, 18 hypertensives without renal or cardiova scular disease were allocated to losartan (50 mg/die for one year) treatmen t. Renal haemodynamic measurements included renal plasma flow (ERPF) and gl omerular filtration rate (GFR) by standardized radioisotope study. Effectiv e renal blood flow (ERBF), filtration fraction (FF), and renal vascular res istance (RVR) were also calculated. Blood pressure was evaluated monthly, w hereas renal haemodynamics and function were detected at baseline and after 6 and 12 months of losartan administration. Losartan induced a significant (p < 0.001) decrease in SBP, DBP, and MBP versus baseline values both at 6 months and at 12 months. In addition a significant decrease in RVR (p < 0. 001) and in FF (p < 0.05) was also seen. In addition RVR values at 1 year o f treatment were higher than their values at 6 months, but this difference was not significant. Our data indicated that long-term control in blood pre ssure induced by losartan administration was associated with a maintained r enal function after 6 months of treatment, but these favourable effects wer e attenuated after 1 year of treatment.