Effects of Fatty Acid Delivery on Heart Metabolism and Function in Type 2 Diabetes

Overview[ - collapse ][ - ]

Purpose Type 2 diabetes mellitus (T2DM) is a disease that interferes with the body's proper production and use of insulin, a hormone needed to convert sugar into usable energy. People with T2DM are at a higher risk for certain cardiovascular diseases, including heart disease and stroke. Normal treatments for T2DM target blood sugar levels only, but there is reason to believe that also targeting blood fat levels will improve both sugar metabolism and heart function in people with T2DM. This study will determine the effectiveness of blood-fat lowering treatments along with blood-sugar control treatments in improving heart function and symptoms of people with T2DM.
ConditionDiabetes Mellitus, Type II
InterventionDrug: Lovaza
Drug: Metformin
PhaseN/A
SponsorWashington University School of Medicine
Responsible PartyWashington University School of Medicine
ClinicalTrials.gov IdentifierNCT00577590
First ReceivedDecember 18, 2007
Last UpdatedAugust 4, 2011
Last verifiedAugust 2011

Tracking Information[ + expand ][ + ]

First Received DateDecember 18, 2007
Last Updated DateAugust 4, 2011
Start DateOctober 2003
Estimated Primary Completion DateDecember 2011
Current Primary Outcome MeasuresImpact of lowering triglycerides in patients with T2DM; the effect of Lovaza on whole body and myocardial substrate metabolism and function [Time Frame: Measured at Year 5] [Designated as safety issue: No]
Current Secondary Outcome MeasuresNot Provided

Descriptive Information[ + expand ][ + ]

Brief TitleEffects of Fatty Acid Delivery on Heart Metabolism and Function in Type 2 Diabetes
Official TitleCyclotron Produced Isotopes in Biology and Medicine, Project 3: Specific Aim 1A and 1B Effects of Fatty Acid Delivery on Myocardial Metabolism and Function in Type 2 Diabetes
Brief Summary
Type 2 diabetes mellitus (T2DM) is a disease that interferes with the body's proper
production and use of insulin, a hormone needed to convert sugar into usable energy. People
with T2DM are at a higher risk for certain cardiovascular diseases, including heart disease
and stroke. Normal treatments for T2DM target blood sugar levels only, but there is reason
to believe that also targeting blood fat levels will improve both sugar metabolism and heart
function in people with T2DM. This study will determine the effectiveness of blood-fat
lowering treatments along with blood-sugar control treatments in improving heart function
and symptoms of people with T2DM.
Detailed Description
T2DM is the most common type of diabetes. In T2DM, the body does not properly process sugars
and, as a result, there is an excess amount of sugar in the blood. Eventually, the high
blood sugar levels can lead to heart disease, nerve damage, kidney problems, or blindness.
Typical T2DM treatments target maintenance of blood sugar levels. Previous studies on T2DM
have indicated that in people who have high amounts of fats in the blood, the body relies
more heavily on fats than sugars as an energy source. This dependence on fats for energy has
been shown to have a negative effect on heart function. There is reason to believe that
lowering the levels of fats in the blood will enhance the ability of the heart and the whole
body to efficiently use both fats and sugars as energy sources. This study will evaluate the
effectiveness of treatment strategies that are designed to reach target levels of sugar and
fat in the blood for treating people with T2DM.

Participation in this double-blind study will last between 4 and 6 months. First,
participants will undergo a medical screening and medication adjustment period, expected to
last 6 months. The medical screening, lasting about 1 hour, will involve completing a
medical history, physical exam, pregnancy test if applicable, and blood test to measure
various factors that contribute to diabetes control. Participants will also be asked
permission to store 1 tablespoon of their blood for up to 10 years to be used in future
studies concerning genetics and heart energy metabolism. During the medication adjustment
period, study physicians will adjust the participants' medications, offer advice on diabetes
education and nutrition, and record any side effects from the medications. For newly
diagnosed T2DM participants, the study physician may recommend medication changes to assure
a hemoglobin A1c (HgA1c) level of less than 7.5%. If participants have already achieved this
level, they will be asked to continue present medications and to also begin taking the
medication metformin for the 30 days before they undergo several imaging studies. Next,
participants will complete routine tests that evaluate the pumping function of the heart,
including an electrocardiogram (ECG) performed before and during exercise, a body
composition study using a dual energy x-ray absorptiometry (DEXA) scan, and a magnetic
resonance imaging (MRI) test. Each of these tests will last between 30 and 90 minutes.

After the qualifying tests, participants will return for the first of two separate imaging
days that will include the same tests. The second imaging day will occur at the end of the
medication period, approximately 2 months after the first imaging day. The first tests will
be a whole body metabolism study and a heart metabolism imaging study, performed
simultaneously. The whole body metabolism study will involve the injection of two tracers of
metabolism, one for glucose and one for fatty acids. The heart metabolism imaging study will
involve a positron-emission tomographic (PET) scan to take pictures of the heart and will
include blood draws. The final imaging test will be a resting echocardiogram (ECHO) to
measure heart function.

Following completion of the first day of imaging tests, participants will be randomly
assigned to one of two possible treatment groups: Group A or B. In addition to continuing
current medications, both groups will begin taking metformin daily. Group A will also take a
pill of Lovaza daily, and Group B will take a matching placebo of Lovaza daily. Participants
will be seen monthly for the next 4 months, during which study medication will be
distributed and blood pressure, heart rate, weight, and any side effects, such as lower
extremity swelling, will be measured. If there is a noticeable increase in swelling, study
physicians may adjust medication dosages. During visits at Months 2 and 4, blood samples
will be taken to measure liver and organ function and HgA1c. At the completion of the
4-month medication treatment, participants will undergo repeat imaging tests. If needed,
participants will be offered the opportunity to attend one or more follow-up visits to
re-establish a medication routine.
Study TypeInterventional
Study PhaseN/A
Study DesignAllocation: Randomized, Endpoint Classification: Pharmacokinetics/Dynamics Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Treatment
ConditionDiabetes Mellitus, Type II
InterventionDrug: Lovaza
Dosage of 4 g to be taken daily for 2 months
Other Names:
Omega-3-acid ethyl ester compoundDrug: Metformin
Dosage of at least 1000 mg to be taken daily for 4 months
Other Names:
Non-thiazolidinedione (TZD) oral agents
Study Arm (s)
  • Experimental: A
    Participants assigned to take metformin and Lovaza
  • Placebo Comparator: B
    Participants assigned to take metformin and placebo

Recruitment Information[ + expand ][ + ]

Recruitment StatusActive, not recruiting
Estimated Enrollment146
Estimated Completion DateDecember 2011
Estimated Primary Completion DateJune 2009
Eligibility Criteria
Inclusion Criteria:

- Meets Americans with Disabilities Act (ADA) criteria for T2DM; if newly diagnosed,
must have fasting blood glucose greater than 126 mg/dl on two occasions, a random
blood glucose greater than 200 mg/dl with symptoms, or a diagnostic oral glucose
tolerance test

- Weight of less than 350 pounds

- Hemoglobin A1c of equal to or less than 7.5% at study entry or willing to go on one
of the following therapies to achieve necessary percentage: metformin monotherapy
greater than 1000 mg daily for at least 30 days or metformin greater than 1000 mg
daily plus any combination of sulfonylurea, glipizide, or alpha-glucosidase inhibitor

- Blood pressure less than 140/90 mm Hg at study entry

- LDL level less than 130 mg/dL if on stable lipid lowering regimen

- Willing to undergo normal rest/stress (treadmill or dobutamine) echocardiogram

- If currently taking thyroid replacement therapy, must be on a stable dose of thyroid
replacement and must have a thyroid function blood test that is in the normal range

- Willing to use an effective form of birth control throughout the study

Exclusion Criteria:

- Received therapy with an insulin sensitizer of the thiazolidinedione class within 6
months prior to study entry

- Required insulin therapy for more than 2 weeks in the year prior to study entry

- History of angina, heart attack, coronary artery bypass grafting (CABG), stroke,
congestive heart failure (CHF), or peripheral vascular disease (PVD)

- Known coronary artery disease (CAD) with residual lesions of greater than 50%

- Current smoker

- Use or expected use of corticosteroids in any form

- Serum triglycerides greater than 400 mg/dl on a fasting sample at study entry

- Any contraindication to a thiazolidinedione (TZD) insulin sensitizer, metformin, or
other drugs likely to be used during the study

- Liver disease with liver function test (LFT) greater than 2 times the upper limit of
normal (ULN)

- Serum creatinine greater than 1.5 mg/dl for women and 1.6 mg/dl for men OR greater
than 2+ proteinuria on urine dipstick
GenderBoth
Ages18 Years
Accepts Healthy VolunteersNo
ContactsNot Provided
Location CountriesUnited States

Administrative Information[ + expand ][ + ]

NCT Number NCT00577590
Other Study ID Numbers487
Has Data Monitoring CommitteeNo
Information Provided ByWashington University School of Medicine
Study SponsorWashington University School of Medicine
CollaboratorsNational Heart, Lung, and Blood Institute (NHLBI)
Investigators Principal Investigator: Robert Gropler, MD Washington University School of Medicine
Verification DateAugust 2011

Locations[ + expand ][ + ]

Washington University in St. Louis
St. Louis, Missouri, United States, 63110