BACKGROUND: Exercise capacity as measured by peak oxygen uptake (Vo₂(peak)) is low in hemodialysis patients. The present study assesses determinants of VO₂(peak) in patients with chronic kidney failure who either changed kidney replacement modality to frequent hemodialysis therapy or received a kidney transplant. STUDY DESIGN: Cohort study with assessment at baseline and 6 months after modality change. SETTING & PARTICIPANTS: Participants included nondiabetic individuals receiving conventional hemodialysis who: (1) remained on conventional hemodialysis therapy (n = 13), (2) changed to short daily hemodialysis therapy (n = 10), or (3) received a transplant (n = 5) and (4) individuals who underwent a pre-emptive transplant (n = 15). Additionally, 34 healthy controls were assessed at baseline only. PREDICTOR: Modality change. MEASUREMENT & OUTCOMES: Exercise capacity, assessed using the physiologic components of the Fick equation (Vo₂ = cardiac output × a-vo₂(dif), where a-vo₂(dif) is arterial to venous oxygen difference) was determined using measurement of Vo₂(peak) and cardiac output during symptom-limited exercise testing. Analysis of covariance was used to compare differences in changes in Vo₂(peak), cardiac output, heart rate, stroke volume, and a-vo₂(dif) at peak exercise between participants who remained on hemodialysis therapy and those who underwent transplant. RESULTS: Transplant was the only modality change associated with a significant change in Vo₂(peak), occurring as a result of increased peak cardiac output and reflecting increased heart rate without a change in peak a-vo₂(dif) despite increased hemoglobin levels. There were no differences in participants who changed to daily hemodialysis therapy compared with those who remained on conventional hemodialysis therapy. LIMITATIONS: Small nonrandomized study. CONCLUSIONS: Vo₂(peak) increases significantly after kidney transplant, but not with daily hemodialysis; this improvement reflects increased peak cardiac output through increased peak heart rate. Despite statistical significance, the increase in Vo₂(peak) was not clinically significant, suggesting the need for interventions such as exercise training to increase Vo₂(peak) in all patients regardless of treatment modality.
BACKGROUND: Exercise capacity as measured by peak oxygen uptake (Vo₂(peak)) is low in hemodialysis patients. The present study assesses determinants of VO₂(peak) in patients with chronic kidney failure who either changed kidney replacement modality to frequent hemodialysis therapy or received a kidney transplant. STUDY DESIGN: Cohort study with assessment at baseline and 6 months after modality change. SETTING & PARTICIPANTS: Participants included nondiabetic individuals receiving conventional hemodialysis who: (1) remained on conventional hemodialysis therapy (n = 13), (2) changed to short daily hemodialysis therapy (n = 10), or (3) received a transplant (n = 5) and (4) individuals who underwent a pre-emptive transplant (n = 15). Additionally, 34 healthy controls were assessed at baseline only. PREDICTOR: Modality change. MEASUREMENT & OUTCOMES: Exercise capacity, assessed using the physiologic components of the Fick equation (Vo₂ = cardiac output × a-vo₂(dif), where a-vo₂(dif) is arterial to venous oxygen difference) was determined using measurement of Vo₂(peak) and cardiac output during symptom-limited exercise testing. Analysis of covariance was used to compare differences in changes in Vo₂(peak), cardiac output, heart rate, stroke volume, and a-vo₂(dif) at peak exercise between participants who remained on hemodialysis therapy and those who underwent transplant. RESULTS: Transplant was the only modality change associated with a significant change in Vo₂(peak), occurring as a result of increased peak cardiac output and reflecting increased heart rate without a change in peak a-vo₂(dif) despite increased hemoglobin levels. There were no differences in participants who changed to daily hemodialysis therapy compared with those who remained on conventional hemodialysis therapy. LIMITATIONS: Small nonrandomized study. CONCLUSIONS: Vo₂(peak) increases significantly after kidney transplant, but not with daily hemodialysis; this improvement reflects increased peak cardiac output through increased peak heart rate. Despite statistical significance, the increase in Vo₂(peak) was not clinically significant, suggesting the need for interventions such as exercise training to increase Vo₂(peak) in all patients regardless of treatment modality.
Authors: Patricia Lynn Painter; Lisa Hector; Karen Ray; Liliana Lynes; Suzanne Dibble; Steven M Paul; Stephen L Tomlanovich; Nancy L Ascher Journal: Transplantation Date: 2002-07-15 Impact factor: 4.939
Authors: Termboon Sangkabutra; David P Crankshaw; Claudia Schneider; Steve F Fraser; Simon Sostaric; Kim Mason; Caroline M Burge; Sandford L Skinner; Lawrence P McMahon; Michael J McKenna Journal: Kidney Int Date: 2003-01 Impact factor: 10.612
Authors: Kathy E Sietsema; William R Hiatt; Anne Esler; Sharon Adler; Antonino Amato; Eric P Brass Journal: Am J Kidney Dis Date: 2002-01 Impact factor: 8.860
Authors: Yoshio N Hall; Brett Larive; Patricia Painter; George A Kaysen; Robert M Lindsay; Allen R Nissenson; Mark L Unruh; Michael V Rocco; Glenn M Chertow Journal: Clin J Am Soc Nephrol Date: 2012-03-15 Impact factor: 8.237
Authors: Elizabeth C Lorenz; Cassie C Kennedy; Andrew D Rule; Nathan K LeBrasseur; James L Kirkland; LaTonya J Hickson Journal: Kidney Int Rep Date: 2021-06-09