ISRADIPINE IN PREDIABETIC HYPERTENSIVE SUBJECTS

OBJECTIVE - Investigators from the Multicenter Isradipine Diuretic Ath erosclerosis Study (MIDAS) previously reported that the isradipine gro up had a higher incidence of cardiovascular disease (CVD) events than the diuretic group. The ultimate objective of the analyses presented h ere was to assess how indices of glycemia (specifically, serum glucose , serum insulin, and HbA(1c)) might have influenced the effects of the two agents on blood pressure control and CVD events. RESEARCH DESIGN AND METHODS - Inclusion criteria included men and women greater than o r equal to 40 years of age with ultrasonographically confirmed carotid atherosclerosis and a diastolic blood pressure of >90 mmHg. Although insulin-dependent diabetic patients were excluded, the three glycemia indices had nide enough ranges to include patients who may be classifi ed as prediabetic. A total of 883 patients were randomized either to t he dihydropyridine calcium antagonist (CA) isradipine (2.5-5 mg twice a day) or to the diuretic hydrochlorothiazide (12.5-25 mg twice a day) and followed in double-blind fashion for 3 years. RESULTS - Both trea tment groups had achieved comparable control of diastolic blood pressu re, and there were no statistically significant differences in any of the glycemia indices, either at baseline or during follow-up. However, the excess isradipine events were noted to be clustered among those p atients with elevated baseline levels of HbA(1c) who also experienced greater blood pressure reductions during follow-up. CONCLUSIONS - The increased cardiovascular risk associated with dihydropyridine CAs in p rediabetic patients may be an explanation for the overall CA debate.