Effect of captopril on blood pressure and kidney function in normotensive insulin dependent diabetics with nephropathy.

Abstract

To assess whether inhibition of angiotensin converting enzyme protects kidney function in diabetic nephropathy. Open, randomised follow up study of normotensive insulin dependent diabetics with nephropathy either treated or not with captopril for one year. Outpatient diabetic clinic in a tertiary referral centre. 32 Normotensive patients with insulin dependent diabetes complicated by nephropathy who were randomised either to the treatment group (n = 15) or to the control group (n = 17). The treatment group was given captopril (25-100 mg/day) for 12 months, the average dose during the second six months of the study being 40 mg daily. Controls were not treated. Albuminuria, arterial blood pressure, and the glomerular filtration rate. Mean arterial blood pressure fell by 3 (SE 2) mm Hg in the captopril treated group and rose by 6 (1) mm Hg in the controls. In addition, albuminuria declined by 11% in the captopril treated group and rose by 55% in the controls, fractional albumin clearance fell by 17% in the captopril treated group and increased by 66% in the controls, and the glomerular filtration rate declined by 3.1 (2.8)ml/min/1.73 m2 with captopril and by 6.4 (3.1) ml/min/1.73 m2 in the controls. Inhibition of angiotensin converting enzyme arrests the progressive rise in albuminuria in normotensive insulin dependent diabetics with nephropathy.