XFIT: An Exercise-based Frailty Intervention in Lung Transplant Candidates

PROJECT ABSTRACT Despite major advances in risk stratification and clinical management, the field of lung transplantation continues to experience persistently high waitlist mortality, increased peri-operative complications, and post- transplant disability, with nearly 1/3 patients dying within 3-years. The NHLBI has deemed the need for

interventions to target causes for these poor outcomes as a priority to advancing the field. Over the last decade, our team has shown that physical frailty is present in up to 1/3 of lung transplant candidates and is associated with markedly increased risk for disability, poorer health-related quality of life, and death both before and after

lung transplantation. Screening for frailty is now recommended as part of clinical lung transplant candidacy evaluations. Once frailty is identified, however, there are no empirically supported treatments to address it. Although the causes of frailty are multifactorial, exercise and lifestyle modification remain gold-standard

frailty treatments as they target key consensus mechanisms of frailty. In observational work, we showed that key mechanisms of frailty—and treatable by lifestyle interventions—such as sarcopenia, adiposity, systemic inflammation, and low physical activity are associated with frailty in lung transplant candidates. With this as

background, we partnered with experts in geriatrics, PR, and exercise physiology to adapt frailty interventions designed for community-dwelling older adults to lung transplant. In two remotely-delivered pilot interventions, we showed that frailty can be treated in small groups of highly selected lung transplant candidates and recipients.

We are now poised to scale our remotely-delivered intervention program to treat frail lung transplant candidates. Our Exercise-based Frailty Intervention in Lung Transplantation (XFIT) program is an 8-week telehealth-delivered exercise-focused intervention. It integrates theoretical frameworks of behavior change to

engage participants in program of “pre-habilitation”. During the R61 milestone-driven development and preparation phase, we will complete trainings, patient-facing materials, finalize the XFIT protocol, recruit a DSMB, and obtain regulatory approvals. During the R33 intervention phase, we will randomize 70 patients who

reflect the diversity and spectrum of illness seen in the general lung transplant candidate population to either XFIT or enhanced standard of care. An interventionalist with expertise in exercise physiology and remote interventions will deliver 8 weekly sessions using video-conference software in participants’ homes. These

sessions feature one-on-one exercise training and targeting of behavioral barriers to optimizing physical activity using motivational interviewing principles. Establishing safety is our primary outcome. We will secondarily establish feasibility and acceptability, and explore responsiveness six-minute walk distance, frailty, PROs . We

anticipate that this first-of-its kind study in solid organ transplantation will establish fundamental safety, feasibility, and accessibility data needed inform larger scale interventions. XFIT directly addresses NHLBI, solid-organ transplant, and respiratory society calls for frailty interventions.