EMERALD: Effects of Metformin on Cardiovascular Function in Adolescents With Type 1 Diabetes (EMERALD)
Diabetes is increasingly common among youth, forecasting early complications. Type 1 (T1D) cause early heart disease, shortening lifespan despite modern improvements in control of blood sugars and other risk factors for heart disease. Poor insulin action, otherwise known as insulin resistance (IR), is the main factor causing heart disease in type 2 diabetes (T2D), but the cause of increased heart disease in T1D is unclear. IR may contribute to heart disease in T1D as in T2D, as the investigators and others have found the presence of IR in T1D. Much less is known about IR in T1D, but a better understanding of its role in T1D is critical to understanding causes of heart disease in T1D. The investigators long-term goal is to understand the early causes of heart disease in diabetes so that we can prevent it. The investigators unique initial findings suggest that even reasonably well-controlled, normal weight, T1D youth are IR. The IR appears directly related to the heart, blood vessel, and exercise defects, but in a pattern that appears very different from T2D. The goals of this study are to determine the unique heart, blood vessel and insulin sensitivity abnormalities in T1D youth, and determine whether metformin improves these abnormalities. A clear understanding of these factors will help determine the causes, and what treatments could help each abnormality.
Hypothesis 1: Metformin will improve insulin function and mitochondrial function in T1D.
Hypothesis 2: Metformin will improve vascular and cardiac function in T1D.
All measures will be performed twice, before and after a 3-month randomized, placebo-controlled design where subjects are randomized to either metformin or placebo. The independent impact of insulin action as well as glucose levels, BMI, T1D duration, and gender on baseline outcomes and the impact of changes in insulin action, glucose levels and BMI on response to metformin will also be examined to help customize future strategies to prevent heart disease in T1D. This study will advance the field by providing new information about the role of poor insulin action in the heart disease of T1D, and whether improving insulin action in T1D is helpful. If a focus on directly improving insulin action in T1D youth is supported by our studies, the clinical approach to T1D management may significantly change.
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
|Official Title:||Effects of Metformin on Cardiovascular Function in Adolescents With Type 1 Diabetes|
- Change in Insulin Function [ Time Frame: 3 months ]Hypothesis 1: Metformin will improve insulin function and mitochondrial function in Type 1 Diabetes. Insulin function will be measured using a euglycemic-hyperinsulinemic clamp procedure at both baseline and after 3 months of treatment.
- Change in Cardiovascular Function [ Time Frame: 3 months ]Hypothesis 2: Metformin will improve vascular and cardiac function in Type 1 Diabetes. Cardiac and vascular function will be measured using echocardiogram and vascular reactivity using inflatable cuffs.
|Study Start Date:||March 2013|
|Estimated Study Completion Date:||March 2018|
|Estimated Primary Completion Date:||December 2017 (Final data collection date for primary outcome measure)|
Placebo Comparator: Metformin
Metformin will be given at a dose of 1000 mg twice a day orally for three months to assess changes in insulin resistance compared to placebo.
Placebo Comparator: Placebo
Placebo will be given at a dose of 1000 mg twice a day orally for three months to assess changes in insulin resistance compared to metformin.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01808690
|United States, Colorado|
|Children's Hospital Colorado and University of Colorado Denver Health Sciences Center|
|Aurora, Colorado, United States, 80045|
|Principal Investigator:||Kristen Nadeau, MD, MS||University of Colorado/Children's Hospital Colorado|