COMPARISON OF THE EFFECTS OF CAPTOPRIL AND NICARDIPINE ON INSULIN SENSITIVITY AND THROMBOTIC PROFILE IN PATIENTS WITH HYPERTENSION AND ANDROID OBESITY

Hypertension is often related to metabolic disorders, such as android obesity, glucose intolerance, dyslipidemia, and hyperinsulinism (X syn drome). Insulin resistance (IR), described as the common link among th ese disorders, could contribute to an increase in coronary risk. The,e uglycemic insulin clamp technique has been used to show that different classes of antihypertensive agents have different effects on IR. The purpose of this multicenter study was to compare the effects of captop ril to those of nicardipine on insulin profile using the oral glucose tolerance test (OGTT), a routine-feasible test. After a 1-month single -blind placebo period, 154 patients with hypertension and android obes ity were randomized to 3 months of double-blind therapy with either 50 mg captopril twice daily (n = 77) or 50 mg nicardipine twice daily (n = 77). An OGTT with an assay of insulin was performed before and afte r active treatment. Lipid parameters, Factor VII (F VII), fibrinogen, plasminogen activator inhibitor 1 (PAI-1), and insulin-like growth fac tor I (IGF-I) were measured at the same time. After 3 months of treatm ent, the changes from baseline in mean +/- SD values for the insulin a rea under the curve (AUC) were -24.8 +/- 107.4 mu IU x h/mL (-15.2%) f or captopril v 6.1 +/- 98.6 mu IU x h/mL (4.8%) for nicardipine (P = . 072). Changes in peak insulin values were -18.3 +/- 86.2 mu IU/mL (-14 %) for captopril v 6.7 +/- 79.4 mu IU/mL (6.6%) for nicardipine (P = . 070). Baseline fasting insulin levels influenced the treatment effect (P = .037), with a greater effect on insulin AUC outcomes for patients with high baseline values in the captopril group (-29%) than in the n icardipine group (P = .011). No difference was observed between the tw o groups in blood pressure variation, PAI-1, IGF-I, F VII, fibrinogen, lipid profile, or glucose AUC. In conclusion, although glucose AUC di d not change, the decrease in insulin AUC after captopril treatment st rongly suggests that insulin sensitivity is improved by captopril inde pendently of its effect on blood pressure reduction.