Influence of Endothelial Function on Central and Peripheral Causes Of Exercise Impairment in Type 2 Diabetes (InsITE)
This study will evaluate the effects of impaired blood flow regulation on exercise. It will also determine whether the effects are more important in the heart or in the skeletal muscle tissue during exercise. In addition, this study will decide whether temporarily reversing these problems will improve blood flow control, improve heart and muscle tissue function and help improve exercise capacity in person with type 2 diabetes. This study will do so using two methods: (1) by giving vitamin C through an IV and (2) a three month exercise training program. Up to 100 subjects will be enrolled in this study.
|Study Design:||Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Health Services Research
|Official Title:||Influence Of Endothelial Function On Central and Peripheral Causes Of Exercise Impairment In Type 2 Diabetes|
- Characterize the purported cardiac dysfunction during exercise in people with type 2 diabetes mellitus (T2DM),evaluate potential changes in cardiac function following 2 interventions: Three months exercise training and acute vitamin C administration. [ Time Frame: 3 years ] [ Designated as safety issue: No ]
|Study Start Date:||May 2008|
|Study Completion Date:||October 2011|
|Primary Completion Date:||October 2011 (Final data collection date for primary outcome measure)|
Experimental: Ascorbic acid
All study subjects have ascorbic acid infusion during one exercise visit as well as a three month exercise training intervention.
Behavioral: Exercise program
Three month exercise program located at the Anschutz Medical Campus at I-225 and Colfax. The program runs three times per week for about an hour each session. Gym is open Monday - Saturday during specific hours (morning, noon, evening).
Other Name: Exercise TrainingDrug: Ascorbic Acid (Vitamin C)
During one exercise study visit, 0.06 g Vit C per kg fat-free mass per 100 ml of normal saline administered; Subjects will receive a bolus of 100mL Vit C solution given at 5ml/min over 20minutes followed by a "drip-infusion" given at 1.7ml/min.
The investigators have found that persons with type 2 diabetes have an impaired ability to perform exercise even without clinically apparent complications. The reasons for this marked abnormality are unknown but are important as the decreased ability to exercise could contribute to the decreased expenditure of physical activity frequently observed in this population and may potentially constitute an early marker of cardiovascular disease.
The investigators wish to evaluate the effects of impaired blood flow regulation on exercise capacity and whether the effects are more important in the heart or in the skeletal muscle tissue during exercise. In addition, the investigators are determining whether correcting these abnormalities by two methods of improving blood flow regulation (acutely infusing Vitamin C or three months of chronic exercise training) leads to improved blood flow regulation, improved heart and skeletal muscle tissue function and hence to better exercise capacity in person with type 2 diabetes. This information will provide a more mechanistic understanding of causes of abnormal exercise responses observed in person with type 2 diabetes as well as whether and to what degree responses are modifiable. Interventions that reverse the exercise defect may facilitate patient adherence to prescribed physical activity programs and potentially decrease cardiovascular mortality in this large segment of the population.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00786019
|United States, Colorado|
|University of Colorado Denver|
|Aurora, Colorado, United States, 80045|
|Principal Investigator:||Judith G Regensteiner, PhD||University of Colorado, Denver|