The Effects of ACE Inhibition on Glucose Tolerance and Insulin Sensitivity in Patients with Hypertension

The probable role of insulin resistance in essential hypertension (EH) and the effects of ACE inhibitors on glucose metabolism (including on the insulin sensitivity) were studied in 15 persons. Nine were hypertensive, 6 were normotensive and nonobese, nondiabetic persons. The two groups exhibited no signifıcant difference regarding age, sex and body mass index. Peripheral insulin sensitivity of both groups was detected by "euglycemic hyperinsulinemic clamp technique" which is generally accepted as first-choice among alternative techniques. In the hypertensive group the mean metabolized glucose amount (Ml), an indirect sign of insulin sensitivity, was found significantly low compared to the normotensive control group, indicating resistance to insulin in essential hypertensive patients, (3.7 ± 0.6 vs 6.9 ± ı .5 mg/kg/min) A long-acting ACE inhibitor (ramipril) was used only in the hypertensive group for 12 weeks and "euglycemic hyperinsulinemic elamp technique" was repeated. M value (M2, 5.3 ± 0.9 mg/kg/min) was significantly higher than the pretreatment value. These findings suggested that insulin resistance has a role in the etiopathogenesis of EH. Furthermore, we concluded that the relationship between EH and insulin resistance is independent of obesity and impaired glucose tolerance and that ACE inhibitors can decrease insulin resistance and improve insulin sensitivity.