Examining Genetic Influence on Response to Beta-Blocker Medications in People With Type 2 Diabetes

Condition(s) targeted: Diabetes Mellitus, Type 2

Intervention: Atenolol (Drug)

Phase: Phase 4

Status: Not yet recruiting

Sponsored by: National Heart, Lung, and Blood Institute (NHLBI)

Official(s) and/or principal investigator(s):
Amber L. Beitelshees, PharmD, MPH, Principal Investigator, Affiliation: University of Maryland

Overall contact:
Amber L Beitelshees, PharmD, MPH, Phone: 410-706-0118, Email: abeitels@medicine.umaryland.edu

Beta-blockers are medications used to treat cardiovascular disease (CVD) symptoms, including high blood pressure and chest pain. People with diabetes who receive beta-blockers may experience adverse health effects, but the exact cause of why this happens remains unknown. This study will examine the genetic factors that may influence how atenolol, a beta-blocker medication, affects fat breakdown, blood sugar levels, and heart function in people with type 2 diabetes.

Official title: Uncoupling Protein Polymorphisms and Cardiometabolic Responses to Beta-Blockers

Study design: Treatment, Open Label, Single Group Assignment

Primary outcome:

Change in diastolic function (annular tissue velocity [Em])

Change in free fatty acid kinetics

Secondary outcome: Change in insulin sensitivity, glucose effectiveness, glucose, insulin, high-density lipoprotein (HDL), or triglycerides

Detailed description: People with diabetes who develop CVD have worse health outcomes than people without diabetes who develop CVD. Beta-blockers are medications used to treat high blood pressure, angina (i. e., chest pain), arrhythmias, and other CVD conditions. While beta-blockers are effective at treating these conditions, they may also have damaging effects on cholesterol or glucose levels, thereby possibly lessening their ability to prevent CVD events in people with diabetes. It is important to identify which patients may not benefit from receiving beta-blocker medications. Genetic factors may influence how people respond to beta-blocker medications. The purpose of this study is to evaluate the influence of genetic variation on beta-blocker-induced changes in insulin sensitivity, fat breakdown, and heart function in people with type 2 diabetes.

This study will enroll people with type 2 diabetes. At a series of up to three baseline study visits, participants will have a blood collection, a glucose tolerance test, an echocardiogram to obtain images of the heart, and biopsies of muscle from the thigh and fat from the stomach. All participants will then receive atenolol once a day for 8 weeks. During Week 1, participants will receive a low dose of atenolol. They will then attend a study visit at the end of Week 1, and study researchers will examine how well participants are tolerating the medication. If the atenolol is well tolerated, the dose will be increased. Study researchers will call participants 1 week after any dosage changes to monitor for side effects. Blood collection will occur again at a study visit at Week 4. At Week 8, participants will then attend up to three study visits for repeat baseline testing. Participants will then be slowly tapered off of atenolol over a 1-week period.

Minimum age: 21 Years. Maximum age: N/A. Gender(s): Both.

Criteria:

Inclusion Criteria:

- Type 2 diabetes for more than 1 year before study entry

Exclusion Criteria:

- Insulin therapy

- Treatment with any beta-blocker in the 30 days before study entry

- Asthma

- Chronic obstructive pulmonary disease (COPD)

- Greater than first degree heart block

- Heart rate less than 60 bpm

- Systolic blood pressure less than 90 mm Hg

- Raynaud's phenomenon

- Known history of angina, heart attack, heart failure, coronary revascularization, or

automatic implantable cardioverter defibrillators

- Pregnant

- Creatinine clearance less than 35 ml/min

- Hematologic dysfunction (white blood cell[WBC] count less than 3000 or hematocrit

less than 28%)

- Allergy to lidocaine

Amber L Beitelshees, PharmD, MPH, Phone: 410-706-0118, Email: abeitels@medicine.umaryland.edu

University of Maryland, Baltimore, Maryland 21201, United States

Starting date: September 2009
Ending date: June 2013
Last updated: August 13, 2009