The Impact of Fitness on Vascular Dysfunction in Adolescents With Type 1 Diabetes

University of Virginia32 enrolled

Overview

The principal hypothesis of this study is that the micro and macro vasculature of young diabetes mellitus type 1 (DM1) patients is particularly susceptible to atherogenic factors which cause vascular dysfunction at multiple levels of the arterial vasculature and that this dysfunction is demonstrable using state-of-the-art ultrasound methods. The investigators further hypothesize that interventions, such as exercise, that are readily integrated into the daily life of individuals with DM1 can mitigate or reverse these early vascular changes and thereby diminish the otherwise predictable longer-term development of cardiovascular disease (CVD) in type 1 DM

Study Type

OBSERVATIONAL

Enrollment

Conditions

Type 1 Diabetes

Interventions

Definity microbubblesDRUG

Definity microbubbles are used as a contrast agent to image blood flow in skeletal muscle

Eligibility

Medical Language ↔ Plain English

Inclusion Criteria: You may be eligible if you are: * Male or female, 12-18 years of age * Healthy, no chronic illness other than DM1 * No medications that would affect the blood vessels * Non-smoker * Normal height and weight Requirements for both groups (study 1) * Two outpatient visits lasting \~1 to 1 ½ hours * 1 outpatient admission lasting \~ 10 hrs * Most visits require blood draws Requirements for second part of study for DM1 group (study 2) * Two additional outpatient visits (one requires blood draw) * 12 weeks of an exercise program (5 days per week, 3 of them here at UVA) * Maintain healthy diet for those 12 weeks-you will have diet instruction * Repeat outpatient admission as described above Exclusion Criteria: * under 12 or over 18 years of age * medication that could affect the blood vessels * smoker * above average BMI * chronic illness other than DM1

Outcomes

Primary Outcomes

arterial vascular stiffness

Arterial Stiffness will be measured as follows: 1. Pulse wave velocity (m/sec) 2. Augmentation index ( %)

Time frame: 2 years

Secondary Outcomes

nitric oxide dependent vasodilation

NO dependent vasodilation will be measured by: 1. Flow Mediated dilation of brachial artery (% of brachial artery diameter change) 2. Post ischemic flow velocity in brachial artery ( m/sec) 3. Forearm microvascular perfusion using contrast ultrasound ( video intensity)