INSULIN SENSITIVITY AND BETA-CELL FUNCTION IN ESSENTIAL-HYPERTENSION AND NORMOTENSIVE FIRST-DEGREE RELATIVES OF HYPERTENSIVE SUBJECTS

We investigated glucose metabolism and beta-cell function in normotens ive subjects with one essential hypertensive parent and in subjects wi th mild/moderate essential hypertension (eHT) before and after 12-week treatment with nitrendipine. The hypertensive-parent group comprised 12 normotensive subjects, and the hypertensive group 15 subjects with mild/moderate eHT. A corresponding control group composed of 20 normot ensive subjects was also investigated. All subjects underwent a freque ntly sampled intravenous glucose tolerance test (FSIGT). Hypertensive subjects underwent FSIGT testing before and after 12 weeks of treatmen t with nitrendipine (20 mg per day). Insulin sensitivity, glucose effe ctiveness and beta-cell function were investigated using the minimal m odel technique on the basis of FSIGT rest data. No significant differe nces were detected in any of the minimal-model parameters either betwe en the hypertensive-parent group and the control, or between the hyper tensive group (before nitrendipine treatment) and the control. Twelve weeks of anti-hypertensive treatment with nitrendipine led to an incre ase in glucose effectiveness and a non-significant increase in glucose tolerance, but had no significant effects on other minimal-model para meters or on the serum lipid profile. Our results suggest that eHT can not be considered consistently associated with insulin resistance. Nit rendipine treatment appears to have no undesirable effects on peripher al sensitivity to insulin or on beta-cell function. However, the 12-we ek course led to a 72 % increase in glucose effectiveness.