EFFECTS OF INTENSIFIED BLOOD-PRESSURE REDUCTION ON RENAL-FUNCTION ANDALBUMIN EXCRETION IN PRIMARY HYPERTENSION - ADDITION OF FELODIPINE ORRAMIPRIL TO LONG-TERM TREATMENT WITH BETA-BLOCKADE

The effect of intensified blood pressure (BP) control with a reduction of the diastolic BP to less than or equal to 85 mm Hg on renal functi on and urinary albumin excretion (UAE) was studied in 28 men with prim ary hypertension (aged 62 to 72 years) treated for 13 +/- 5 years with beta-blockade, diuretics, or hydralazine. They were compared with 25 normotensive (NT) men of similar age. At baseline (BL), glomerular fil tration rate (GFR), renal plasma flow (RPF) (clearance of inulin and p ara-aminohippurate), and the UAE were studied. Thereafter, all antihyp ertensive drugs except beta-blockers were withdrawn and either felodip ine (5 to 20 mg; n = 13) or ramipril (2.5 to 10 mg; n = 15) was added in a double blind, randomized fashion. Hydrochlorothiazide was added i f necessary. The investigations were repeated after 6 weeks and 1 year of double-blind treatment. At BL, the BP and the renal vascular resis tance (RVR) were significantly higher and GFR and RPF were significant ly lower in both hypertensive groups than in NT. After 1 year, the BP treatment goal was reached by all patients in the felodipine group but only by two-thirds in the ramipril group in spite of addition of diur etics to 60% of the latter group. In the felodipine group, the BP, GFR , and RVR after 1 year no longer differed significantly from normal. T he UAE and the fractional albumin clearance increased significantly af ter 1 year's treatment in the felodipine group but did not change in t he ramipril group. The fractional albumin clearance, however, did not differ significantly from normal either at BL or after 1 year's treatm ent in any of the hypertensive groups.It is therefore possible to redu ce BP and improve renal function in primary hypertension to levels not significantly different from normal after treatment with felodipine i n combination with beta-blockade. Although this regimen increased the low UAE slightly, the fractional albumin clearance changed less and di d not differ significantly from normal. The ramipril/beta-blocker comb ination reduced BP less and did not change the slightly reduced renal function or the UAE.