Exercise-based prehab improves functional outcomes in kidney transplant candidates

An 8-week exercise-based prehabilitation program helps enhance exercise capacity, muscle function, and muscle size in kidney transplant candidates, including those with frailty, according to the FRAILMar study.

FRAILMar included 121 individuals (mean age 63.4 years, 76 percent male) on the kidney transplant waiting list, of which 40 percent had frailty (Fried phenotype ≥2). These individuals were randomly assigned to undergo the study intervention (intervention group) or receive standard care (control group). The intervention was a prehabilitation program involving 24 exercise sessions. Each session lasted an hour and conducted three times per week for 8 weeks.

Exercise capacity, the primary outcome, was evaluated via maximal workload during a cardiopulmonary exercise test. Secondary outcomes included peripheral muscle function, respiratory muscle function, muscle size, and changes in frailty status.

A total of 106 patients completed the prehabilitation program. The intervention group showed significantly greater improvements in exercise capacity compared with the control group (12.8 watts, 95 percent confidence interval [CI], 3.4–22.2; p=0.008).

Similarly, participants in the intervention had significantly greater handgrip strength (1.8 kg, 95 percent CI, 0.7–2.8; p<0.001) and rectus femoris thickness (1.2 mm, 95 percent CI, 0.3–2.0; p=0.007) relative to those in the control group.

The subgroup of frail patients who underwent the intervention vs control also had significant improvements across most measures, demonstrating potential benefits of prehabilitation for this subgroup.

The study had several limitations, including the short follow-up duration and the risk of type I error due to multiple comparisons, even though outcomes were prespecified.