Comparison of the effects of an angiotensin converting enzyme inhibitor and a calcium antagonist in hypertensive, macroproteinuric diabetic patients : a randomised double-blind study

The objective of this study was to compare the effects of an angiotensin converting enzyme inhibitor, lisinopril, with those of a calcium blocker, nifedipine, on BP control and renal function, in a prospective randomised double-blind, double-dummy trial lasting 19 weeks in patients with diabetic nephropathy. We enrolled 28 diabetic patients with hypertension and macroproteinuria from the out-patient diabetic-renal clinic. The antihypertensive treatment consisted of lisinopril or nifedipine, and their effect on arterial BP, urinary albumin excretion, glomerular filtration rate, and renal blood flow were measured. BPs at entry were 166/99 (SD 23/9) mmHg for the lisinopril group and 165/99(21/7) mmHg for the nifedipine group. BPs fell to 143/88 (17/13) mmHg for the lisinopril group and 148/85(25/10) mmHg for the nifedipine group at the end of the study. The albumin excretion rate fell in the lisinopril group from 738.7 (635.2) micrograms/min to 644.6 (965.2) micrograms/min and rose in the nifedipine group from 981.2 (1022.2) micrograms/min to 1072.5 (908.5) micrograms/min (P = NS). Glomerular filtration rates fell from 105.2 (57.5) ml/min per 1.73 m2 to 72.1 (39.4) ml/min per 1.73 m2 in the lisinopril group and from 109.9 (50.0) ml/min per 1.73 m2 to 82.9 (53.9) ml/min per 1.73 m2 in the nifedipine treated group. Renal blood flow fell from 446.8 (217.9) ml/min per 1.73 m2 to 435.1 (243.3) ml/min per 1.73 m2 for the lisinopril group and from 473.0 (216.4) ml/min per 1.73 m2 to 419.0 (278.6) ml/min per 1.73 m2 for the nifedipine group. Differences between the groups were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)