Effect of captopril or imidapril on the progression of diabetic nephropathy in Japanese with type 1 diabetes mellitus: a randomized controlled study (JAPAN-IDDM)

Abstract 

Objective: to clarify and confirm the renoprotective effects of ACEIs in Japanese type 1 diabetics. Research design and methods: a double-blind randomized study using two ACEIs, imidapril (a prodrug of imdaprilat without an SH-residue) and captopril as well as placebo was performed. Seventy-nine eligible cases were randomized to receive captopril 37.5 mg (n=26), imidapril 5 mg (n=26) or their placebos (n=27) daily in a double-blind manner. Results: urinary albumin excretion (UAE), determined every half year, was significantly decreased by the ACEIs (placebo vs. ACEIs F=11.316, P=0.001, placebo vs. captopril F=4.260, P=0.043, placebo vs. imidapril F=14.341, P<0.001) during the study period (the mean; 1.48 years). Although the HbA_1C levels and systolic blood pressure (BP) between the three groups were not different, glycemic and BP control significantly affected UAE. Systolic BP in the placebo group tended to be higher by 7–10 mmHg throughout the study. Conclusions: these results suggest that the ACE inhibitors, imidapril and captopril, prevent the increase in UAE in micro and macroalbuminuric patients with type 1 diabetes mellitus and that the target BP might be less than 130/80 mmHg.

Keywords: Diabetes mellitus, Imidapril, Captopril

Abbreviations: ACEIs, angiotensin converting enzyme inhibitors, BP, blood pressure, UAE, urinary albumin excretion