Vascular Effects of Carvedilol Versus Metoprolol in Hypertensive Patients With Type 2 Diabetes

Phase 4

Completed

Brief Summary: The purpose of this study is to compare the vascular effects of two commonly used blood pressure medications, carvedilol and metoprolol in hypertensive patients with type 2 diabetes.

Detailed Description: Carvedilol and metoprolol are two commonly used blood pressure medications that have both been shown to be effective in controlling hypertension. Although in the same drug class, preliminary data have shown that these medications may have different vascular effects. This study will assess which medication is better at improving artery health independent of their blood pressure lowering effects. Artery health will be assessed non-invasively by ultrasound. Certain markers of atherosclerosis found in the blood will also be measured.

Recruitment & Eligibility

Inclusion Criteria

Age 30-80 years old
Documented history of type 2 diabetes
Stable angiotensin converting enzyme/angiotensin receptor blocker (ACE/ARB) regimen 30 days before and throughout the study period
Stable anti-diabetic regimen throughout the study period
Body mass index (BMI) between 22-45 kg/m2
HbA1c between 6-9% for patients on anti-diabetic treatment regimen and HbA1c between 6-8% for patients who are being controlled by diet alone
Screening blood pressure (BP) > 130/80 (average of 3 sitting measurements), with current medications

Exclusion Criteria

Uncontrollable or symptomatic arrhythmias
Unstable angina
Sick sinus syndrome or second or third degree heart block
Decompensated heart failure
Myocardial infarction (MI) or stroke within 3 months of screening
Bradycardia
Chronic obstructive pulmonary disease (COPD) with required inhaled or oral bronchodilators or corticosteroids
Bronchial asthma or related bronchospastic conditions
New onset/diagnosed type 2 diabetes (<3 months)
Clinically significant renal or liver disease (creatinine >2.5 mg/dL)
Endocrine disorders
Use of anorectic or other diet drugs inconsistent with recommendations for type 2 diabetics
Use of beta-blockers within 3 months of screening
Use of corticosteroids
Systemic disease, including cancer, with reduced life expectancy (<12 months)
Psychological illness/condition that interferes with comprehension of study requirements
Use of an investigational drug within 30 days of entry into study

Arm && Interventions

Group	Intervention	Description
Carvedilol	Carvedilol	Carvedilol, orally, 25 mg, twice daily for five months
Metoprolol	Metoprolol	Metoprolol, orally, 200 mg, twice daily for five months.

Primary Outcome Measures

Name	Time	Method
Flow Mediated Dilation	change from baseline to 5 months	Flow mediated dilation is a measure of endothelial function. It is measured by the percent change in artery diameter (i.e. dilation), pre and post manual artery occlusion.

Secondary Outcome Measures