#2831 A randomised controlled study of a Combined Home-based ExERcISe and Nutritional ApproacH to improve frailty in kidney transplant recipients (CHERISH)
Authors: Chan Winnie , Donnelly James , Greig Carolyn , Borrows Richard 
Published: May 2024

Abstract

Background and Aims
Post-transplantation frailty is common, with a prevalence of up to 52% in kidney transplant recipients (KTRs), and is associated with increased mortality, recurrent hospitalisation and inferior quality of life (QoL). Resistance exercise training (RET) was found to improve frailty in this patient group. Both high and low protein intakes were associated with potential risk of graft failure. To date, no studies have evaluated the safety and efficacy of RET combined with protein supplementation (RETPS) in KTRs. The objectives of this study were to investigate the effect of RETPS on kidney function and frailty status in KTRs, and assess its impact on QoL.

Method
Forty clinically stable KTRs ≥1 year post-transplantation [mean age = 54 ± 14 years; 50% male, median time post-transplantation = 7 years] were enrolled and randomised to either RET (n = 20) or RETPS (n = 20). All participants completed a 30-minute home-based progressive RET regimen 2-3 times weekly for 12 weeks, guided by an exercise worksheet and a study-specific video link. Participants received weekly telephone call to ensure safety and compliance of the interventions. The RETPS group received additional body-weight adjusted whey protein supplementation 1-hour post exercise. Total daily dietary protein intake did not exceed 1.40 g/kg/day to confine to a safe level of protein consumption in KTRs. Kidney function was measured by estimated glomerular filtration rate (eGFR), creatinine, and albumin-creatinine ratio (ACR). Frailty was evaluated using Fried Frailty Phenotype (FFP), Short Performance Physical Battery (SPPB), 60-second Sit-to-Stand test (60s-STST), handgrip- (HG) and back-leg-chest- (BLC) derived muscle strength, bioimpedance-derived lean tissue index (LTI), and ultrasound-derived thigh muscle thickness (TMT). QoL was assessed using Short Form (SF) -36 questionnaire. All measurements were performed at baseline and at week 12.

Results
Kidney function did not differ significantly between baseline and week 12 in both RET [eGFR: 62.1 vs 59.7 ml/min; creatinine: 107.3 vs 111.5 μmol/L; ACR: 12.8 vs 10.4 mg/mmol] and RETPS [eGFR: 61.2 vs 60.7 ml/min; creatinine: 101.1 vs 102.2 μmol/L; ACR: 17.6 vs 20.9 mg/mmol] groups. Frailty status assessed by FFP and SPPB improved in both RET [FFP: 2.5 vs 1.3, P &lt; .001; SPPB: 7.2 vs 11.6, P &lt; .001] and RETPS [FFP: 2.8 vs 1.1, P &lt; .001; SPPB: 6.4 vs 10.9, P &lt; .001] groups, but the improvements did not differ significantly between groups (P &gt; 0.23). Improvements in 60s-STST, HG-derived muscle strength, BLC-derived muscle strength, and ultrasound-derived TMT were observed in both RET [60s-STST: 23 vs 27, P &lt; .001; HG-derived muscle strength: 24 vs 30 kg, P &lt; .001; BLC-derived muscle strength: 62 vs 71 kg, P &lt; .001; ultrasound-derived TMT: 15 vs 19 mm, P &lt; .001] and RETPS [60s-STST: 20 vs 29, P &lt; .001; HG-derived muscle strength: 24 vs 32 kg, P &lt; .001; BLC-derived muscle strength: 57 vs 80 kg, P &lt; .001; ultrasound-derived TMT: 14 vs 21 mm, P &lt; .001] groups, with greater improvements in RETPS group for 60s-STST (P &lt; .01), HG-derived muscle strength (P &lt; .05), BLC-derived muscle strength (P &lt; .05), and ultrasound-derived TMT (P &lt; .001). For bioimpedance-derived LTI, improvement was observed only in RETPS group [12.8 vs 14.8 kg/m2, P &lt; .05]. SF-36-derived overall-, physical- and mental- related QoL improved in both groups (P &lt; .05 for all), with RETPS group reporting a greater improvement in physical-related QoL (P &lt; .05).

Conclusion
This represents the first study demonstrating RET combined with protein supplementation is safe and effective in improving frailty and QoL in KTRs. Protein supplementation augments increased muscle mass and strength beyond RET effect, further enhancing improvement in physical-related QoL.