The effects of increasing doses of enalapril on insulin sensitivity in normotensive non-insulin dependent diabetic subjects.

BACKGROUND

There are conflicting reports about the effects of ACE inhibitors (ACEI) on insulin sensitivity and glycaemic control. Most studies have used a standard high dose of an ACEI but there have been no studies reported to establish whether any changes in glycaemic control or insulin sensitivity associated with ACEI are dose-related.

AIM

To examine the effect of increasing doses of enalapril on insulin sensitivity in normotensive non-insulin dependent diabetic subjects.

METHODS

The effects of increasing doses of enalapril on insulin sensitivity in ten normotensive non-insulin dependent diabetic subjects were measured, using the hyperinsulinaemic isoglycaemic clamp technique. Following a baseline study, enalapril was commenced at 5 mg daily and increased to 10 mg daily then 20 mg daily at 14 day intervals. Repeat studies were undertaken after 14 days at each dosage.

RESULTS

There was a significant dose-related reduction of systolic blood pressure with enalapril. In contrast enalapril at 5-20 mg daily produced no significant changes in insulin mediated glucose uptake (M-value) or insulin sensitivity index (ISI).

CONCLUSIONS

These findings indicate that in this insulin resistant population of normotensive non-insulin dependent diabetics, angiotensin converting enzyme inhibition with enalapril has no significant effect on insulin mediated glucose uptake.