Short-term aerobic exercise and vascular function in CKD stage 3: a randomized controlled trial.

BACKGROUND: The present study was designed to determine the effect of short-term moderate-intensity exercise training on arterial stiffness in patients with chronic kidney disease (CKD) stage 3. STUDY DESIGN: Randomized controlled trial with a parallel-group design. SETTING & PARTICIPANTS: Testing and training sessions were performed at Springfield College. 46 (treatment group, n=25; control group, n=21) patients with CKD with diabetes and/or hypertension completed the study. INTERVENTION: The aerobic training program consisted of 16 weeks of supervised exercise training at 50%-60% peak oxygen uptake (Vo2peak) 3 times per week, while the control group remained sedentary. Identical testing procedures were performed following the 16-week intervention. OUTCOMES: The primary outcome was arterial stiffness. Secondary outcomes were aerobic capacity, various blood parameters (endothelin 1, nitrate/nitrite, and high-sensitivity C-reactive protein), and health-related quality of life. MEASUREMENTS: Arterial stiffness was assessed with aortic pulse wave velocity (PWV), aerobic capacity by Vo2peak, blood parameters by enzyme-linked immunosorbent assays, and health-related quality of life by the 36-Item Short Form Health Survey (SF-36). Participants attended 4 sessions before being randomly assigned to either the treatment or control group. Participants gave consent during the first session, whereas a graded exercise test with measurement of Vo2peak was completed during the second session. During sessions 3 and 4, aortic PWV was measured at rest prior to 40 minutes of either moderate-intensity exercise training or seated rest. A venous blood sample was obtained prior to exercise or rest and participants completed the SF-36 questionnaire. RESULTS: 16 weeks of training led to an 8.2% increase in Vo2peak for the treatment group (P=0.05), but no changes in aortic PWV . LIMITATIONS: Randomization was not concealed and was violated on one occasion; also, use of an indirect measurement of endothelial function and the short duration of the intervention. CONCLUSIONS: Short-term moderate-intensity exercise training does not alter arterial stiffness in patients with CKD, but seems to reduce endothelin 1 levels.