Abstract: TH-PO548

Effect of Exercise Intensity on Renal Blood Flow in Patients with CKD Stage 2

Session Information

Category: Chronic Kidney Disease (Non-Dialysis)

  • 307 CKD: Health Services, Disparities, Prevention

Authors

  • Koutoku, Kazuko, Fukuoka University, Fukuoka, Japan
  • Yasuno, Tetsuhiko, Fukuoka University School of Medicine, Fukuoka, Japan
  • Kawakami, Syotaro, Fukuoka University Chikusa Hospital, Fukuoka, Japan
  • Saito, Takao, Sanko Clinic, Fukuoka, Japan
  • Matsuda, Takuro, Fukuoka University Hospital, Fukuoka, Japan
  • Fujimi, Kanta, Fukuoka University Hospital, Fukuoka, Japan
  • Uehara, Yoshinari, Fukuoka University, Fukuoka, Japan
  • Higaki, Yasuki, Fukuoka University, Fukuoka, Japan
  • Tanaka, Hiroaki, Fukuoka University Institute for Physical Activity, Fukuoka, Japan
Background

The 2014 American College of Sports Medicine (ACSM) guidelines recommend that patients with chronic kidney disease (CKD) perform moderate intensity aerobic exercise for 20-60 min per day, 3-5 days per week. Several studies have shown that aerobic and resistance exercise improve exercise capacity, muscular strength, left ventricular function, blood pressure, and cardiovascular function in patients with CKD. However, few studies have specifically assesed the risks of exercise specific to CKD patients. In particular, exercise causes a decrease in renal blood flow (RBF), as well as a less marked and more variable decrease in glomerular filtration rate (GFR). The purpose of this study was to determine the association of RBF with intensity of exercise in patients with CKD stage 2.

Methods

Eight males with CKD stage 2 (eGFRcys : 60-89/min/1.73m2) participated in the study, consisting of three separate experiments using a cycle ergometer. In the first experiment, participants performed a maximal graded exercise test. In the second, they performed a multi-stage exercise test to determine their lactate threshold (LT). In the third, they performed a multi-stage exercise test (4 minutes/stage) at intensities of 60%, 80%, 100%, 120%, and 140% of LT. RBF was assessed by Duplex ultrasound (Aplio 300,TOSHIBA, Japan).

Results

The maximal graded exercise test resulted in a 53% reduction in RBF and a significant increase in the filtration fraction (FF) after strenuous exercise (100% of VO2peak). RBF did not significantly decrease until 100%LT was attained, and showed significant decreases of 64% at 120%LT and 62% at 140%LT relative to its resting value (p<0.01). FF also did not change until the LT was reached. In addition, LT corresponded with anaerobic threshold, 40% heart rate reserve, and 55%VO2peak.

Conclusion

Our results demonstrate that RBF and FF do not change during exercise until the LT is attained. These findings may assist in making appropriate exercise intensity recommendations to patients with CKD stage 2.

Funding

  • Private Foundation Support