Effects of Losartan and Diltiazem on Blood Pressure, Insulin Sensitivity, Lipid Profile and Microalbuminuria in Hypertensive Type 2 Diabetic Patients

Abstract

Objective: To investigate the effect of losartan versus diltiazem on blood pressure, albuminuria, insulin sensitivity and lipid profile in a randomised, open study. p ]Patients: 40 type 2 diabetic patients (57 ± 12 years) from the Endocrinology clinic, with mild hypertension, persistent microalbuminuria and normal renal function, were randomly administered losartan 50 mg/day (n = 20) or diltiazem 300 mg/day (n = 20) for 12 weeks. After 1 month, hydrochlorothiazide 12.5mg was added if blood pressure was >130/85mm Hg. Outcome Measures: At baseline and after 3 months, plasma glucose, glycated haemoglobin (HbA1C), uric acid, lipid profile, albumin excretion rate and creatinine clearance were measured by routine methods. Insulin sensitivity was estimated by an insulin suppression test, and ambulatory blood pressure was monitored for 24 hours. Results: Mean systolic blood pressure decreased from 151 ± 15 to 133 ± 11mm Hg with losartan (p < 0.05) and from 153 ± 17 to 130 ± 18mm Hg with diltiazem (p < 0.05). Mean diastolic blood pressure decreased from 82 ± 12 to 74 ± 13mm Hg with losartan (p < 0.05) and from 85 ± 13 to 72 ± 16mm Hg with diltiazem (p < 0.05). Albuminuria decreased from 147 ± 56 to 121 ± 57 μg/min with losartan (p < 0.05) and from 143 ± 76 to 119 ± 49 μg/min with diltiazem (p < 0.05). Differences between the two treatments were not significant. Insulin sensitivity and lipid profile were not modified by any of the treatments and no adverse effects were reported. Conclusion: Both drugs were well tolerated and effectively reduced blood pressure and albuminuria, but did not modify insulin sensitivity or lipid profile.