Glucose Metabolism during Captopril Mono- and Combination Therapy in Diabetic Hypertensive Patients: A Multiclinic Trial

The effects of captopril monotherapy and combination therapy with thiazide diuretics or with methyldopa on glucose tolerance test (GTT) were investigated in 71 diabetic hypertensives. After the baseline evaluation, captopril (37.5-75 mg/day) was given. GTT and insulin assay were performed again between 10 and 12 weeks after the initiation of captopril therapy. We also studied the effects of chronic captopril therapy (6-12 months) on GTT in patients with essential hypertension. Captopril was well tolerated in all patients and no adverse reactions were observed. Chronic captopril therapy produced a significant (p < 0.01) fall of blood pressure in all patients. There was no significant deterioration of the insulinogenic index or the time course curves of plasma glucose and insulin after GTT. These results indicate that captopril therapy does not affect glucose metabolism. Thus captopril may have an advantage for clinical use in hypertensive patients with or without impaired glucose metabolism.