Kidney Week

Abstract: FR-PO192

Aerobic Exercise Improves Vascular Function in Non-Dialysis CKD

Session Information

• Vascular Biology and Dysfunction
  November 03, 2017 | Location: Hall H, Morial Convention Center
  Abstract Time: 10:00 AM - 10:00 AM

Category: Hypertension

• 1103 Vascular Biology and Dysfunction

Authors

• Kirkman, Danielle L., University of Delaware, Newark, Delaware, United States

Danielle L. Kirkman,

• Ramick, Meghan G., University of Delaware, Newark, Delaware, United States

Meghan G. Ramick,

• Muth, Bryce J., University of Delaware, Newark, Delaware, United States

Bryce J. Muth,

• Stock, Joseph M, University of Delaware, Newark, Delaware, United States

Joseph M Stock,

• Townsend, Raymond R., University of Pennsylvania School of Medicine , Villanova, Pennsylvania, United States

Raymond R. Townsend,

• Edwards, David G., University of Delaware, Newark, Delaware, United States

David G. Edwards,

Background

Endothelial dysfunction is a cardiovascular disease risk factor (CVD) characteristic of chronic kidney disease (CKD). This study investigated the effect of aerobic exercise on vascular function in Stage 3-5 CKD.

Methods

In this randomized controlled trial, 36 patients (eGFR 44±2ml/min/1.73m²) were randomized to an Exercise Training (EXT) or Control (CON) arm. EXT consisted of 3x45min of supervised exercise per week at 60-85%HRR for 12 weeks whereas CON received routine care. Outcomes were assessed at 0 and 12 weeks. VO_2peak was assessed by cardiopulmonary exercise testing. Conduit artery function was assessed via brachial artery flow mediated dilation (FMD). Microvascular function was assessed via cutaneous vasodilation during local heating coupled with intradermal microdialysis measured by laser Doppler flowmetry. Participants were instrumented with 3 microdialysis fibers for the delivery of 1) Ringer’s solution; 2) superoxide scavenger Tempol; 3) NADPH oxidase inhibitor Apocynin. Cutanoues vascular conductance was calculated as a percent of maximum achieved with sodium nitroprusside infusion.

Results

A training response was indicated by an increase in VO_2peak following EXT (Week 0 vs. 12; EXT:17.9±1.2 vs. 19.9±1.60ml/kg/min, p=0.05; CON:18.2±1.7 vs. 17.4±1.6ml/kg/min, p=0.1). Brachial artery FMD was maintained and cutaneous microvascular function was improved following EXT compared to CON (Figure 1). At baseline, pharmacological delivery of Apocynin and Tempol improved microvascular function (Ringer’s vs. Apocynin vs. Tempol:85±1% vs. 90±1% vs. 90±1%, p=0.02) but was no longer effective following EXT (91±2% vs. 87±2% vs. 87±2%, p=0.03), suggesting that reduced oxidative stress plays a role in vascular improvements following EXT.

Conclusion

Aerobic exercise improves vascular function and could be implemented as an adjunct therapy to reduce CVD risk in non-dialysis CKD patients.

Figure 1 A Cutaneous vasodilation response to heating at the Ringer's microdialdysis site (interaction p=0.04) B Brachial artery flow mediated dilation (interaction p=0.02)

Funding

• Other NIH Support