Kidney Week

Abstract: SA-PO432

Optimal Protocol for Cardiopulmonary Exercise Testing (CPET) in Patients on Dialysis

Session Information

• Hemodialysis and Frequent Dialysis - 2
  October 26, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Dialysis

• 801 Dialysis: Hemodialysis and Frequent Dialysis

Authors

• Groninger, Nolan, Indiana University School of Medicine, Indianapolis, Indiana, United States

Nolan Groninger

• Arroyo, Eliott, Wake Forest University, Winston-Salem, North Carolina, United States

Eliott Arroyo, PhD

• Burney, Heather, Indiana University School of Medicine, Indianapolis, Indiana, United States

Heather Burney, MS

• Narayanan, Gayatri, Indiana University School of Medicine, Indianapolis, Indiana, United States

Gayatri Narayanan, MS

• Karp, Sharon L., Indiana University School of Medicine, Indianapolis, Indiana, United States

Sharon L. Karp, MD, MPH

• Lim, Kenneth, Indiana University School of Medicine, Indianapolis, Indiana, United States

Kenneth Lim, MD, PhD, FASN

Background

Patients with end-stage kidney disease (ESKD) on hemodialysis commonly present with impaired physical function which is linked to adverse outcomes including frailty, fractures, reduced quality of life, and mortality. Peak oxygen uptake (VO₂Peak) is usually obtained by standard ramp incremental testing, but this protocol may underestimate VO₂Peak. To determine the most accurate method for obtaining VO₂Peak in patients on dialysis, we sought to compare the ramp protocol with two novel CPET protocols, the self-paced (SP), and RISE (ramp incremental step exercise) that are considered alternative options to the traditional incremental ramp test.

Methods

We analyzed data from the ongoing “Comparison of the Self-Paced versus Ramp Incremental Exercise Protocols on Patients with Kidney Failure (SPARK)” study, a randomized cross-over study comparing patients on dialysis versus healthy controls. Participants completed three CPET protocols on three separate visits: 1) standard ramp 2) SP (five 2-min stages with self-selected workload) and 3) RISE. Testing was completed for patients with ESKD on a non-dialysis day. A repeated measures ANOVA test was performed to compare VO₂Peak values between each protocol.

Results

A cohort of 11 ESKD patients (n=5 men, mean [SD] age=49 [10] years, dialysis vintage=30 [IQR: 10-48] months) and 21 healthy controls (n=10 men, age=55 [9] years) participated in the study. No significant differences in sex or age were observed (P>0.05) but there was significant difference in race (P=0.003) and ethnicity (P=0.002). There was no significant difference in VO₂Peak between protocols in ESKD patients (ramp=13.5 [1.2] mL/min/kg; SP=13.2 [0.9] mL/min/kg; RISE=13.2 [0.8] mL/min/kg; P=0.77). However, there were significant differences in healthy controls (ramp=30.3 [1.4] mL/kg/min; SP=28.7 [1.4] mL/min/kg; RISE=30.9 [1.2] mL/min/kg; P=0.017). Time-varying covariates remained the same across all visits.

Conclusion

We found that the RISE protocol resulted in higher VO₂Peak averages in healthy controls, but there were no differences in VO₂Peak values between the three protocols in ESKD patients. Therefore, the ramp protocol is the most established CPET methodology and should be selected for objectively determining cardiovascular functional capacity in patients with ESKD.