Decrease of exercise-induced microalbuminuria in patients with type I diabetes by means of an angiotensin-converting enzyme inhibitor.

Taking into account both the importance of microalbuminuria (MA) as a predictive parameter of clinical nephropathy in diabetic patients and the efficiency of exertion to show and/or to increase MA in both diabetic patients and normal individuals, we studied 37 type I diabetic patients divided into two groups: group A, with no MA at rest (n = 19), and group B, with MA at rest (n = 18). Group C comprised 10 healthy volunteers as controls. Changes of basal MA during exercise and postexercise were studied in all three groups. Normotensive patients with no metabolic disorders, normal renal function, and no proteinuria underwent an ergometric test up to 600 kg. This test was repeated after the administration of 20 mg enalapril in a single daily dose for 60 days. Body weight, systolic and diastolic arterial pressure, creatinine, and creatinine clearance were determined and showed no significant variations either between groups or with treatment. Microalbuminuria was studied in the three groups with and without administration of enalapril throughout the 2 months of the study. Determinations were performed under conditions of rest, exercise, and postexercise. Mean baseline MA values +/- SEM were as follows: at rest, 5.22 +/- 0.49, 58.36 +/- 13.24, and 4.73 +/- 0.45 micrograms/min for groups A, B, and C, respectively; with exercise, 15.19 +/- 4.43, 74.70 +/- 14.89, and 16.76 +/- 4.62 micrograms/min for groups A, B, and C, respectively; and postexercise, 32.04 +/- 6.64, 253.15 +/- 63.88, and 9.23 +/- 3.25 micrograms/min, respectively. The geometric means of the baseline to posttreatment MA ratio were as follows: at rest, 0.95, 1.59 (P < 0.01), and 1.03 for groups A, B, and C, respectively; with exercise, 1.53 (P < 0.01), 1.91 (P < 0.01), and 1.69 for groups A, B, and C, respectively; and postexercise, 2.94 (P < 0.01), 3.24 (P < 0.01), and 1.03 for groups A, B, and C, respectively. In conclusion, in the early diagnostic suspicion of diabetic nephropathy, the screening of postexercise MA during an ergometric test could be of help. Treatment with enalapril decreased MA in diabetic groups A (no MA at rest) and B (MA at rest) during exercise and postexercise, and also decreased MA in group B while at rest.

Angiotensin converting enzyme inhibitors versus calcium antagonists in the treatment of diabetic hypertensive patients.

Angiotensin converting enzyme inhibitors and calcium antagonists are effective agents for controlling high blood pressure in diabetic patients. We selected 30 type II diabetic patients with proteinuria and evaluated the effect of these drugs on renal function and proteinuria. In a double-blind trial, patients received either 40 mg/day enalapril or 40 mg/day nifedipine during 12 months. They also received a hypoproteic diet with 0.8 g/kg wt/day of protein. In the enalapril group (10 men and eight women), mean arterial blood pressure was 112.0 +/- 12 mm Hg, creatinine clearance was 58.6 +/- 12.4 ml/min, and 24-hour proteinuria was 4.36 +/- 3.23 g/24 hr before treatment. After treatment, mean arterial blood pressure was 82.0 +/- 8.30 mm Hg (p less than 0.001), creatinine clearance was 66.6 +/- 13.8 ml/min (NS), and 24-hour proteinuria was 0.56 +/- 0.78 g/24 hr (p less than 0.001). In the nifedipine group (six men and six women), mean arterial blood pressure was 114.0 +/- 8.0 mm Hg, creatinine clearance was 67.8 +/- 19.6 ml/min, and 24-hour proteinuria was 2.84 +/- 1.31 g/24 hr before treatment. After treatment, mean arterial blood pressure was 86.0 +/- 7.0 mm Hg (p less than 0.001), creatinine clearance was 51.4 +/- 7.9 ml/min (p less than 0.001), and 24-hour proteinuria was 2.66 +/- 0.89 g/24 hr (NS). These results show a similar hypotensive action and different renal effects between these two drugs after 12 months of treatment.

Enalapril improved renal function and proteinuria in chronic glomerulopathies.

Ten patients (6 men, 4 women, age range 35-64 years) with glomerulopathies were studied. Diagnoses were membranoproliferative glomerulonephritis (GN; n = 4), membranous GN (n = 3), focal and diffuse glomerulosclerosis (n = 2), and poststreptococcal GN (n = 1). These were confirmed by renal biopsy in 8 of the 10 patients. All patients had reduced function (creatinine clearance 15-55 ml/min); proteinuria ranged from 1.0 to 10.4 g/day. Three normotensive patients received enalapril 10 mg once daily. Seven hypertensives received enalapril 10-40 mg once daily to control blood pressure (BP). Concomitant diuretic therapy (furosemide/bumetanide) was administered to 6 patients. There were visits every 14 days for a mean of 15.9 months (range 9-26 months). Diet was monitored, and BP was significantly controlled in the hypertensive patients but not altered in the normotensives. Serum creatinine, blood urea nitrogen, creatinine clearance, and 24-hour urinary protein improved and did not deteriorate progressively. Serum potassium did not change significantly. No adverse clinical events were noted. Enalapril therapy may improve the prognosis for GN over time by maintaining glomerular filtration rate and decreasing proteinuria.

Effects of enalapril on renal parameters in patients with primary glomerulopathies associated with chronic renal failure.

14 patients (8 male, 6 female), aged 35 to 64 years, with glomerulopathies consisting of membranoproliferative glomerulonephritis (GN) [n = 6], membranous GN (n = 3), focal and diffuse glomerulosclerosis (n = 4), and post-streptococcal GN (n = 1) were studied. Diagnosis was established by renal biopsy in 12 of the 14 patients. All 14 patients had impaired renal function (creatinine clearance = 25 to 55 ml/min) and proteinuria (1.0 to 10.4 g/day). Five normotensive patients received enalapril 20 mg/day, whereas 9 patients with hypertension received 20 to 40 mg/day to control blood pressure. Diuretics were administered concomitantly to 8 patients. Patients attended the clinic every 14 days for 30 months and their diets were closely monitored, with sodium intake limited to between 50 and 100 mEq/day and protein to between 1.0 and 1.2 g/kg/day. Blood pressure was significantly controlled in the patients with hypertension. Serum creatinine, blood urea nitrogen, creatinine clearance and 24-hour urinary protein excretion all significantly improved during the 30-month study. No adverse clinical events were noted. Thus, over a period of time, enalapril therapy may improve the prognosis of patients with glomerulonephritis by maintaining glomerular filtration rates and decreasing proteinuria and blood pressure.