The aim of our prospective study was to evaluate putative progression promoters, kidney function, and prognosis during long-term treatment with
angiotensin-converting enzyme inhibition in
insulin-dependent diabetes mellitus patients suffering from
diabetic nephropathy. Eighteen consecutive hypertensive
insulin-dependent diabetes patients with nephropathy (mean age, 33 years) who had not been treated previously were all treated with
captopril in combination with
frusemide or
bendrofluazide. The four patients who were refractory to this regimen also received
nifedipine. Treatment was continued for a median of 8.9 years (range, 6.3 to 9.8, years). Renal function was assessed every 6 months by measurement of glomerular filtration rate (GFR) (single-bolus 51Cr-EDTA technique) and
albuminuria by radioimmunoassay. Baseline values (+/- SE) were mean arterial blood pressure 146/93 +/- 3/1 mm Hg,
albuminuria (geometric mean +/- antilog SE) 982 +/- 1.2 micrograms/min, and GFR 98 +/- 5 mL/min/1.73 m2.
Angiotensin-converting enzyme inhibition induced a significant reduction during the whole treatment period of blood pressure (137/85 +/- 3/1 mm Hg; P < 0.01) and
albuminuria (392 +/- 1.4 microns/min; P < 0.01), and the rate of decline in GFR was 4.4 +/- 0.7 mL/min/yr, in contrast to previous reports of 10 to 14 mL/min/yr (natural history). Univariate analysis revealed a significant correlation between the rate of decline in GFR and mean arterial blood pressure (r = 0.58, P = 0.01),
albuminuria (r = 0.67, P < 0.01),
hemoglobin A1c (r = 0.69, P < 0.01), and serum total
cholesterol concentration (r = 0.51, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)