Effect of Exercise on Endothelial Function and Vascular Compliance in Chronic Kidney Disease
The study hypothesis is that 6 weeks of repetitive handgrip exercise will improve endothelial function and venous compliance in pre-dialysis patients with an estimated glomerular filtration rate of less than or equal to 20 ml/min. If proven correct then arm exercise might be useful to improve the success rate for a surgically created arteriovenous fistula in the forearm to become usable as a vascular access for hemodialysis.
|Study Design:||Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Basic Science
|Official Title:||Effect of Forearm Exercise on Flow Mediated Vasodilation Prior to Arteriovenous Fistula Placement for Hemodialysis|
- Brachial artery flow-mediated dilatation [ Time Frame: 6 weeks ] [ Designated as safety issue: No ]
- Forearm venous compliance by plethysmography [ Time Frame: 6 weeks ] [ Designated as safety issue: No ]
|Study Start Date:||January 2007|
|Study Completion Date:||June 2010|
|Primary Completion Date:||May 2008 (Final data collection date for primary outcome measure)|
Experimental: Repetitive handgrip exercise
After baseline testing and randomization, subjects in this group are instructed to perform the intervention: daily repetitive handgrip exercise with upper arm compression band. Brachial artery endothelial function and venous compliance are tested at baseline and 6 weeks.
Other: Repetitive arm exercise
After baseline testing and randomization, subjects in this group are instructed to perform repetitive handgrip exercise with an upper arm compression band until arm fatigue occurs. After resting 1 minute this exercise is repeated 9 times daily for 6 weeks.
No Intervention: No arm exercise
Time control. Subjects do usual activities without any exercise intervention. Brachial artery endothelial function and venous compliance are tested at baseline and 6 weeks.
An arteriovenous fistula (AVF) is the optimal vascular access for chronic hemodialysis. However, AVFs frequently fail to mature. Better strategies are needed to promote AVF maturation. Successful AVF maturation involves arterial and venous dilation. Arterial dilation depends on endothelial release of nitric oxide which can be measured by brachial artery flow-mediated dilation (FMD) and has been reported to predict successful AVF maturation. Venous dilation depends on venous compliance which can be measured by venous plethysmography and is also predictive of successful AVF maturation. Endothelial function is impaired in patients with chronic kidney disease (CKD). Aerobic exercise has been reported to improve endothelial function and venous compliance but it has not been studied in the pre-dialysis patient. To address this question we will determine whether 6 weeks of repetitive handgrip exercise with upper arm venous compression can improve brachial artery endothelial function or venous compliance in pre-dialysis patients with an estimated glomerular filtration rate of less than or equal to 20 ml/min.
|United States, Iowa|
|University of Iowa General Clinical Research Center|
|Iowa City, Iowa, United States, 52242|
|Principal Investigator:||Bradley S Dixon, MD||University of Iowa|