The purpose of this study is to compare losartan and benazepril in diabetic patients whose high blood pressure is not controlled by amlodipine and its relationship to statin current use.

Hypertension and diabetes mellitus are important risk factors for cardiovascular morbidity and mortality. Endothelial dysfunction and vascular rigidity are two pathophysiological mechanisms that may explain this relationship. Recent publications showed that both ACEi (angiotensin-converting enzyme inhibitor-induced) and ARB (angiotensin receptor blocker) were capable of improving vascular stiffness and endothelial function, and that these effects occurred despite blood pressure reduction.

This study main objective is to assess if ARB (losartan) effects are different from ACEi (benazepril) in endothelial function in patients with diabetes mellitus type 2 and blood pressure not controlled by amlodipine and its relationship to statin current use.

Secondary analysis of vascular stiffness will be measured by pulse wave velocity and augmentation index. Echocardiographic parameters, such as indexes of diastolic function, will also be measured.

Inclusion Criteria:

• Ambulatorial patients with age between 40 and 70 years-old.
• Systemic arterial hypertension previously diagnosed and in use of two or less anti-hypertensive drugs in the preceding 4 weeks.
• Type 2 diabetes mellitus in use of oral medication that were not changed in the preceding 4 weeks. Glycated hemoglobin A1c less than 9.0%.
• Accepted the consent form.

Exclusion Criteria:

• Office systolic blood pressure equal or more than 180 mmHg, with or without treatment
• Office diastolic blood pressure equal or more than 110 mmHg, with or without treatment
• Evidences of a secondary cause for hypertension
• Glycated hemoglobin A1c > 9.0%
• Insulin therapy
• Chronic kidney disease stage 4 or 5 or in dialysis
• Advanced target organ lesion, obtained by history or additional exams, and defined by: previous myocardial infarction, heart failure with ejection fraction less than 40%, cerebral vascular accident (ischemic or hemorrhagic), peripheral vascular disease (claudication or doppler with obstruction > 50% of vascular lumen), retinopathy with visual loss, symptomatic neuropathy.
• Cardiac arrhythmias, except for ectopic beats
• Any clinical or disabling condition that, in the opinion of the investigators, may confound or prejudice study results.
• Severe mitral regurgitation.
• Women in fertile age without contraceptive methods in use.
• Breastfeeding women.