EFFECT OF ACE-INHIBITORS ON INSULIN SENSI TIVITY - A CRITICAL-REVIEW

The metabolic effects of angiotensin converting enzyme inhibitors have bren examined in a number of studies. A correct quantitative measurem ent of insulin sensitivity is only possible with help of the glucose c lamp technique. Using a ''Medline'' search we identified all studies t hat used this method to measure the influence of ACE inhibitors on ins ulin sensitivity. We found ten studies and evaluated them according to the following criterias: comparison to another antihypertensive agent , measurement and maintenance of serum potassium concentrations. study design. study size, statistical methods, glucose clamp method employe d, kind of insulin sensitivity index used. The studies were performed on different types of patients: patients with IDDM or NIDDM, patients with essential hypertension and normal controls. Only in two studies t he effects of ACE inhibitors were compared to that of another antihype rtensive agent (diuretic) resulting in a comparable drop in blood pres sure. Serum potassium concentrations were maintained constant during i nsulin sensitivity measurement and throughout the study in one of two studies. This was the only study in which the methods used could stand up to a critical appraisal. In this study no effects of ACE inhibitor administration on insulin sensitivity could be registered.