Kidney Week

Abstract: SA-PO576

Body Composition and Its Response to Intradialytic Exercise in Kidney Failure: A Combined Analysis of the PEDAL and CYCLE-HD Randomised Controlled Trials

Session Information

• Hemodialysis: Biomarkers, Translational Research
  November 04, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Dialysis

• 801 Dialysis: Hemodialysis and Frequent Dialysis

Authors

• Ng, Khai Ping, University Hospitals of Derby and Burton NHS Foundation Trust, Derby, United Kingdom

Khai Ping Ng,

• Macdonald, Jamie Hugo, Institute for Applied Human Physiology, Bangor, United Kingdom

Jamie Hugo Macdonald,

• Young, Robin, University of Glasgow, Glasgow, Glasgow, United Kingdom

Robin Young,

• March, Daniel Scott, University of Leicester, Leicester, United Kingdom

Daniel Scott March,

• Graham-Brown, Matthew, University of Leicester Department of Cardiovascular Sciences, Leicester, United Kingdom

Matthew Graham-Brown,

• Mercer, Tom, Queen Margaret University Division of Dietetics Nutrition Biological Sciences Physiotherapy Podiatry and Radiography, Musselburgh, United Kingdom

Tom Mercer,

• Greenwood, Sharlene A., King's College London Centre for Nephrology Urology & Transplantation, London, United Kingdom

Sharlene A. Greenwood,

• Burton, James, University of Leicester Department of Cardiovascular Sciences, Leicester, United Kingdom

James Burton,

• Dasgupta, Indranil, University Hospitals Birmingham NHS Foundation Trust, Birmingham, Birmingham, United Kingdom

Indranil Dasgupta,

Background

Patients with kidney failure on hemodialysis (HD) are at high risk of sarcopenia obesity, highlighting the need for effective nutrition and exercise strategies to improve long-term outcomes. This post-hoc analysis of the PEDAL and CYCLE-HD studies aimed to 1) determine the clinical utility of fat tissue index (FTI) and lean tissue index (LTI) in comparison to body mass index (BMI) and 2) assess the effect of a 6-month intradialytic exercise intervention on FTI and LTI compared to usual care.

Methods

BMI, FTI and LTI were a priory secondary endpoints in both the PEDAL and CYCLE-HD trials. BMI was classified as per WHO definitions. FTI and LTI were determined by Bioelectrical Impedance Analysis (BIA) and classified as per the MONDO study, that found an FTI of 4-15kg/m² and an LTI of 15-20kg/m² were associated with best survival.

Results

Across both studies, 298 participants had BIA measurement at baseline; with 209 at baseline and 6-months. Mean age was 58±15 years, 65% male, median HD vintage 1.3 years (IQR 0.5-3.4) and mean BMI of 28.3±6.3kg/m². BMI correlated with FTI (r=0.79; p<0.0001). Of those with healthy BMI (n=198), 17% were over-nourished by FTI (>15kg/m²) and 74% undernourished (LTI <15kg/m²). Conversely, among those with an FTI of 4-15kg/m², 14% were categorised as overweight or obese by BMI. There was no significant correlation between BMI and LTI; 24% had BMI ≥30kg/m² and LTI <15kg/m² (sarcopenic obesity); only 16% had both FTI of 4-15kg/m² and an LTI of 15-20kg/m². With intradialytic exercise, there was no significant difference between the groups in change over 6 months for LTI (-0.33, CI -1.08-0.41; p=0.4) or FTI (0.16, CI -0.69-1.00; p=0.7), regardless of compliance.

Conclusion

This study highlighted issues of body composition misclassification using conventional BMI cut-offs in HD patients. Only a minority of patients had both LTI and FTI within the range associated with best survival. The majority of patients had hidden sarcopenia with nearly 75% with normal BMI being sarcopenic. 6-months of intradialytic exercise did not improve body composition, suggesting alternative interventions are required to target fat and lean tissue mass and enhance patients' survival.