Kidney Week

Abstract: SA-OR77

Oxygen Consumption Recovery Is Delayed After the Long Interdialytic Period

Session Information

• Nutritional and Lifestyle Interventions to Promote Health in CKD
  November 04, 2023 | Location: Room 109, Pennsylvania Convention Center
  Abstract Time: 05:51 PM - 06:00 PM

Category: Health Maintenance, Nutrition, and Metabolism

• 1500 Health Maintenance, Nutrition, and Metabolism

Authors

• Arroyo, Eliott, Indiana University School of Medicine, Indianapolis, Indiana, United States

Eliott Arroyo, PhD

• Dillman, Drake, Indiana University School of Medicine, Indianapolis, Indiana, United States

Drake Dillman,

• Coggan, Andrew R., Indiana University Purdue University Indianapolis, Indianapolis, Indiana, United States

Andrew R. Coggan,

• Sher, Syed Jawad, Indiana University School of Medicine, Indianapolis, Indiana, United States

Syed Jawad Sher,

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

Sharon L. Karp,

• Moe, Sharon M., Indiana University School of Medicine, Indianapolis, Indiana, United States

Sharon M. Moe,

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

Kenneth Lim,

Background

Prolonged interdialytic periods leading to accumulation of uremic toxins and volume changes may be associated with alterations in ventilatory response to exercise. O₂ uptake (VO₂) kinetics during the early recovery period on cardiopulmonary exercise testing (CPET) have strong prognostic value in patients with heart failure and have the advantage of being independent of achieving maximal volitional effort. In this study, we sought to examine the effects of the long interdialytic interval on VO₂ kinetics.

Methods

We analyzed data from the ongoing, “Effects of long interdialytic intervals on Cardiovascular Functional Capacity (ECON)” study, a randomized crossover trial of patients on conventional HD. CPET was performed on three study visits: post-HD (baseline; BL), and at the end of a 2-day and the 3-day interdialytic intervals. VO₂recovery (%) was calculated using the following formula: (VO₂peak−VO₂ at minute 1 of recovery)/VO₂peak.

Results

A total of 30 patients (n=19 men, mean [SD] age=54 [11] years, dialysis vintage=71.1 [63] months) were included in this analysis. No differences between visits were observed in VO₂Peak (BL=1.00 [IQR: 0.84-1.14] L/min; 2-day=0.96 [0.83-1.22] L/min; 3-day=0.99 [0.87-1.20] L/min; p=0.71) nor in VO₂ at ventilatory threshold (BL=0.67 [0.15] L/min; 2-day=0.67 [0.15] L/min; 3-day=0.68 [0.14] L/min; p>0.9). However, post-HD fatigue limited the patients’ effort during the BL CPET, as reflected by a lower peak respiratory exchange ratio compared to non dialysis day visits (p=0.014). VO₂Recovery was lower during the 3-day interval (20 [9] %) compared to BL (25 [8] %; p=0.013), while no differences were observed between the 2-day interval (22 [11] %) and BL (p=0.11). Additionally, heart rate (p=0.044) and minute ventilation (p=0.025) after 1 minute of recovery were higher during the 3-day interval compared to BL.

Conclusion

The long interdialytic period may be associated with slowed replenishment of energy stores in peripheral muscles as reflected by the delay in VO₂ and ventilation recovery following maximal exercise. VO₂Peak assessment the same day following HD may be confounded by post-HD fatigue, therefore exercise recovery kinetics may provide incremental prognostic data and unveil subclincial pathophysiological alterations occurring during interdialytic intervals.

Funding

• NIDDK Support – Dialysis Clinic, Inc.