DECREASE OF EXERCISE-INDUCED MICROALBUMINURIA IN PATIENTS WITH TYPE-IDIABETES 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 diabe tic patients and normal individuals, we studied 37 type I diabetic pat ients divided into two groups: group A, with no MA at rest (n = 19), a nd group B, with MA at rest (n = 18). Group C comprised 10 healthy vol unteers as controls. Changes of basal MA during exercise and postexerc ise were studied in all three groups. Normotensive patients with no me tabolic disorders, normal renal function, and no proteinuria underwent an ergometric test up to 600 kg. This test was repeated after the adm inistration of 20 mg enalapril in a single daily dose for 60 days. Bod y weight, systolic and diastolic arterial pressure, creatinine, and cr eatinine clearance were determined and showed no significant variation s either between groups or with treatment. Microalbuminuria was studie d in the three groups with and without administration of enalapril thr oughout the 2 months of the study. Determinations were performed under conditions of rest, exercise, and postexercise. Mean baseline MA valu es +/- SEM were as follows: at rest, 5.22 +/- 0.49, 58.36 +/- 13.24, a nd 4.73 +/- 0.45 mu g/min for groups A, B, and C, respectively; with e xercise, 15.19 +/- 4.43, 74.70 +/- 14.89, and 16.76 +/- 4.62 mu g/min for groups A, B, and C, respectively; and postexercise, 32.04 +/- 6.64 , 253.15 +/- 63.88, and 9.23 +/- 3.25 mu g/min, respectively. The geom etric 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, resp ectively; with exercise, 1.53 (P < 0.01), 1.91 (P < 0.01), and 1.69 fo r 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 co nclusion, in the early diagnostic suspicion of diabetic nephropathy, t he screening of postexercise MA during an ergometric test could be of help. Treatment with enalapril decreased MA in diabetic groups A (no M A at rest) and B (MA at rest) during exercise and postexercise, and al so decreased MA in group B while at rest. (C) 1996 by the National Kid ney Foundation, Inc.