Effect of Exercise on Endothelial Function and Vascular Compliance in Chronic Kidney Disease
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.
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.
Inclusion Criteria:

 -  Age exceeding the age of majority (18 years of age).

 -  Chronic renal failure with a calculated GFR (MDRD equation) less than or equal to 20
 ml/min

 -  Eligible for creation of an arteriovenous fistula for the purpose of hemodialysis.

 -  The subject is expected to stay within driving distance of study site for at least 4
 months.

 -  The subject's physician(s) will allow the patient to participate.

 -  Ability to give informed consent.

 Exclusion Criteria:

 -  Unstable angina.

 -  Uncontrolled hypertension (resting blood pressure >170 systolic or >100 diastolic).

 -  Musculoskeletal or neurologic problem that prevents arm exercise.

 -  Currently functioning arteriovenous access in the same arm as the planned new fistula.

 -  Subjects who are eligible to participate in the ongoing DAC fistula trial.

 -  Planned new access surgery in less than 6 weeks

 -  Anticipated non-compliance with medical care based on physician judgment.

 -  Patient refusal.