Metabolic Effects of Long-term Treatments With Nifedipine-Retard and Captopril in Young Hypertensive Patients

Abstract The objective of this study was to clarify potential differences in the metabolism of glucose and lipids in a long-term treatment (for 5 years) for hypertension among nifedipine-retard and captopril in young, nonobese hypertensive men (HT). In 78 previously untreated HT who were given nifedipine-retard and in 81 HT given captopril, blood pressure (BP), pulse rate, blood glucose, and plasma insulin levels were measured every 30 min for 2 h after 75 g oral glucose ingestion, every year for 5 years. Twenty-six age- and body mass index (BMI)-matched normotensive men (NT) were measured for the same variables for 5 years. They were also measured for total cholesterol, triglyceride levels, and lipids fractions after an overnight fast, every year for 5 years without any kinds of lipid lowering agents. At 1 year after treatment with nifedipine-retard or captopril, BP decreased significantly, and the reductions in BP did not differ between HT treated with nifedipine-retard and captopril. In the entry period, fasting insulin (P< .05), the area under the curve (AUC) of insulin (P< .01), AUC of blood glucose (P< .05) after 75 g oral glucose ingestion, fasting total cholesterol (P< .05), and triglyceride levels (P< .05) in HT were significantly greater than those in NT. In HT treated with captopril, AUC of insulin (P< .01), AUC of blood glucose (P< .05), and total cholesterol (P< .05) decreased significantly after 1 year of treatment for HT, and triglyceride (P< .05) decreased significantly after the 2 year treatment. Although in HT treated with nifedipine-retard, AUC of insulin (P< .01) and AUC of blood glucose levels (P< .05) decreased significantly after 1 year of treatment, triglyceride and total cholesterol levels did not decrease throughout the 5 years. These results indicate that captopril has ameliorative effects in hyperinsulinemia or reduced insulin sensitivity, hypercholesterolemia, and hypertriglyceridemia starting at 1 year after the treatment for HT, whereas nifedipine-retard has an ameliorative effect in the metabolism of glucose but not in the metabolism of lipids. Therefore, ACE inhibitor has additional ameliorative effects on insulin sensitivity to the vasodilatory action.