Effect of manidipine and delapril on insulin sensitivity in type 2 diabetic patients with essential hypertension

Abstract

The open trial was designed to evaluate the effects of long-term antihypertensive treatment with the calcium-channel blocker, manidipine and the angiotensin converting enzyme (ACE) inhibitor, delapril on insulin sensitivity in Japanese non-insulin dependent diabetes mellitus (NIDDM) patients with essential hypertension. We measured the insulin sensitivity index (S I) and the glucose-effectiveness (S G) by the use of Bergman's minimal model method in 18 hypertensive NIDDM patients before and after administration of manidipine (group A) or delapril (group B) for 3 months. Manidipine treatment for 3 months significantly improved S I in group A from 3.35 ± 0.61 (× 10 −4 min −1 μU −1 ml −1) to 4.70 ± 1.34 ( P < 0.05). Delapril treatment for 3 months also significantly improved S I in group B from 3.56 ± 1.04 to 5.00 ± 0.87 ( P < 0.05). Manidipine significantly improved S G in group A from 1.60 ± 0.64 (× 10 −2 min) to 2.19 ± 0.38 ( P < 0.05). Delapril treatment also significantly improved S G in the group B from 1.41 ± 0.56 to 1.91 ± 0.35 ( P < 0.05). Manidipine and delapril did not affect urinary C-peptide excretion for 24 h in the hypertensive NIDDM patients. Treatment with manidipine or delapril significantly reduced systolic and diastolic blood pressures in the hypertensive NIDDM patients. There were no differences between plasma glucose, serum total triglycerides, and cholesterol or lipoprotein cholesterol fractions, heart rate and body weight after 3 months on manidipine or delapril. This study confirmed the improving effects on S I and S G by long-term treatment with manidipine or delapril in the hypertensive NIDDM patients.