Comparison of the hemodynamic and metabolic effects of low-dose hydrochlorothiazide and lisinopril treatment in obese patients with high blood pressure

Patients with high blood pressure tend to be insulin resistant, glucose intolerant, hyperinsulinemic, and dyslipidemic. Since these metabolic defects are accentuated by obesity, we thought it important to compare the effects of 3 monthsʹ treatment with either lisinopril (20 mg/day) or low dose hydrochlorothiazide (12.5 mg/day) on blood pressure and glucose, insulin, and lipoprotein metabolism in obese patients with hypertension. There were 14 patients in each group, and they were similar (mean ± SE) in age (54 ± 3 υ 50 ± 4 years), gender (nine men/five women), and body mass index (33.4 ± 0.8 υ 33.9 ± 0.9 kg/m2). Patients treated with lisinopril had a somewhat greater fall in both systolic (18 ± 3 υ 10 ± 3 mm Hg) and diastolic (12 ± 2 υ 8 ± 1 mm Hg) blood pressure, but only the change in systolic pressure was statistically significant (P< .05). Plasma glucose, insulin, and triglyceride concentrations were measured at hourly intervals from 8 am to 4 pm (breakfast at 8 am and lunch at 12 pm), and there was a modest increase in all three variables following hydrochlorothiazide treatment (P< .05 to P< .09). However, daylong plasma glucose, insulin, and triglyceride concentration did not change with lisinopril treatment. Finally, neither the ability of insulin to mediate glucose disposal nor fasting lipid and lipoprotein concentrations, changed with either treatment. In conclusion blood pressure decreased significantly following treatment with either lisinopril (20 mg/ day) or hydrochlorothiazide (12.5 mg/day). Both treatments were associated with little or no untoward effect on multiple aspects of glucose, insulin, and lipoprotein metabolism that increase risk of coronary heart disease, although these metabolic variables did increase somewhat in hydrochlorothiazide-treated patients.