Abstract
Background.
Frailty is a modifiable risk factor for morbidity and mortality among kidney transplant (KT) candidates. We previously demonstrated that an 8-wk center-based exercise intervention is associated with improved frailty parameters in patients with advanced chronic kidney disease. This study aimed to adapt the intervention for home-based delivery and examine its feasibility, safety, and acceptability in a multicenter cohort of KT candidates.
Methods.
We conducted a prospective pilot study between January 2021 and November 2023 involving KT candidates from Mayo Clinic in Minnesota and Baylor St. Luke’s Medical Center in Texas. Adults approved for KT who were (1) frail or prefrail by the Physical Frailty Phenotype and/or (2) had a Short Physical Performance Battery score ≤10 were enrolled. The exercise intervention consisted of an individualized exercise prescription provided by a Mayo Clinic exercise physiologist followed by 8 weekly phone calls. Feasibility was assessed via retention rates, adverse events were recorded, and acceptability was assessed via survey.
Results.
Baseline characteristics of the 15 enrolled participants included a median age of 64 y, 73.3% were men, and 73.3% were of White race. Sixty percent of participants completed the intervention. No unanticipated adverse events occurred. Most participants strongly agreed that the exercise intervention was beneficial to their overall health.
Conclusions.
This pilot study demonstrates that a home-based 8-wk exercise intervention is a promising prehabilitation strategy in KT candidates and provides important preliminary data for future larger, randomized studies.
The clinical significance of frailty in kidney transplantation (KT) candidates is well established. KT candidates who are frail are more likely to experience adverse posttransplant outcomes, including delayed graft function, longer hospital length of stay, rehospitalizations, immunosuppression intolerance, and death.1,2 What is not well established is how to treat frailty in KT candidates. Studies involving non-KT populations have demonstrated that interventions involving preoperative exercise (“prehabilitation”) can improve frailty and postoperative outcomes.3,4 Unfortunately, the transplant community lacks effective prehabilitation interventions for KT candidates. Because of the paucity of available interventions, both the American Society of Transplantation and the European Society of Organ Transplantation have issued consensus statements calling for their development.5,6
We previously developed an 8-wk center-based exercise intervention that was associated with improved frailty parameters in patients with advanced chronic kidney disease, including KT candidates.7 Although promising, our center-based exercise intervention was limited by the need for participant travel to and from the center. This travel requirement can be a barrier to participation for patients who live far away, lack transportation, or have busy schedules. Home-based interventions are a promising alternative to center-based interventions because patients do not need to leave their homes to exercise.
Although home-based exercise interventions have shown promise in non-KT populations, they are understudied in KT candidates. In this study, we adapted our previously studied 8-wk center-based exercise intervention for home-based delivery. This study aimed to examine the feasibility, safety, and acceptability of this 8-wk home-based exercise intervention in KT candidates from 2 different transplant centers. We also explored the sustainability of exercise 1 mo after intervention completion and the relationship between the intervention and exploratory endpoints, including change in frailty and health-related quality of life.
MATERIALS AND METHODS
Patient Population
We conducted a prospective, multicenter study involving patients from Mayo Clinic in Rochester, Minnesota, and Baylor St. Luke’s Medical Center in Houston, Texas. Participants were recruited between January 2021 and November 2023. The study was approved by the Mayo Clinic and Baylor College of Medicine Institutional Review Boards in accordance with the Declaration of Helsinki and was registered on ClinicalTrials.gov (NCT04745169). All participants provided written informed consent.
Potentially eligible individuals who were approved for KT alone at either center were identified from clinical databases. Similar to our prior 8-wk center-based exercise study,7 eligibility criteria consisted of the following: (1) age 18 y and older, (2) ability to consent to research, (3) English-speaking, and (4) frail or prefrail according to the Physical Frailty Phenotype or a Short Physical Performance Battery score ≤10 (see Frailty Testing section).8,9 Patients with significant comorbidities limiting rehabilitation potential, including pulmonary disease requiring continuous oxygen supplementation, active angina, critical aortic stenosis, decompensated heart failure, and known ventricular arrhythmia, were excluded. Enrolled participants received parking passes for each of the 2 study visits and remuneration. Participant demographics, including age, sex, race/ethnicity, smoking history, dialysis history, and diabetes, were ascertained via self-report or abstraction from the electronic medical record.
Frailty Testing
Frailty testing was performed in-person by trained study personnel before the 8-wk exercise intervention (“baseline”) and after completion of the 8-wk exercise intervention (8 wk; Figure 1). Frailty testing included both the Physical Frailty Phenotype and the Short Physical Performance Battery. The Physical Frailty Phenotype consists of 5 criteria: unintentional weight loss during the past year, self-reported exhaustion, low physical activity, slow walking speed, and weak grip strength.8 According to published guidelines, participants meeting ≥3 criteria were defined as frail, participants meeting 1–2 criteria were defined as prefrail, and participants meeting no criteria were defined as not frail. The Short Physical Performance Battery is a composite measure of 3tests of lower extremity function: balance, gait speed, and chair stand.10 According to published guidelines, participants received scores ranging from 0 to 4 for each of the 3 component tests. Component scores were then summed to calculate a total Short Physical Performance Battery score ranging from 0 to 12, with lower scores indicating worse frailty.10
FIGURE 1.
Study design. KDQOL-SF, Kidney Disease Quality of Life Short Form.
Exercise Equipment
Upon enrollment, participants received exercise equipment to use at home, including a pedal exerciser (Vive Health, Naples, Florida, if participant weight <220 lbs or Desk Cycle, Greeley, Colorado, if participant weight ≥220 lbs) and a set of 5 color-coded resistance bands of varying resistance (Norco, North Coast Medical Inc, Morgan Hill, CA). Participants also received printed instructions regarding the use of the pedal exerciser and resistance bands and educational materials from the Mayo Clinic regarding exercise. Specifically, the educational materials contained information regarding individual strength training exercises, including mini-squats, sit to stand, chair or standing marching, biceps curls, triceps extensions, toe raises, and seated straight leg raises. The educational materials also included specific flexibility training exercises, including arm raises, arm circles, shoulder rolls, head turns, trunk rotations, side bends, calf stretches, and hamstring stretches. Finally, participants received an exercise log on which to record their exercise during the duration of the study.
8-wk Exercise Intervention
An overview of the study design is depicted in Figure 1. The 8-wk exercise intervention consisted of a baseline phone call from a Mayo Clinic exercise physiologist followed by 8 weekly phone calls from a Mayo Clinic exercise physiologist. Exercise physiologist phone calls were semiscripted and lasted ≤30 min in duration. During the baseline phone call, the exercise physiologist assessed the participant’s current level of physical activity, discussed stretching and flexibility exercises, and reviewed the Borg Rating of Perceived Exertion.11 During the baseline phone call, the exercise physiologist also provided each participant with an individualized exercise prescription, which focused on the core components of physical activity counseling and exercise training according to guidelines from the American Heart Association and the American Association of Cardiovascular and Pulmonary Rehabilitation12 and consisted of 3 components: (1) aerobic exercise, (2) strength training, and (3) flexibility training. The individualized exercise prescription was also provided to participants in written format at the beginning of the intervention. Recommended aerobic exercises included arm and/or leg ergometry using the study-provided pedal exerciser or other aerobic exercise available to the participant, and recommended resistance training included the study-provided resistance bands. Participants were encouraged to work toward obtaining at least 30 min of moderate-intensity physical activity at least 5 d per week. They were asked to log information regarding their exercise sessions on a study-provided exercise log, including type of exercise, duration and frequency, and associated Borg Rating of Perceived Exertion.11
The 8 weekly exercise physiologist phone calls began 1 wk after the baseline phone call. During the 8 weekly phone calls, the exercise physiologists reviewed goals set during the previous phone call and what the participant had done to work toward those goals. The exercise physiologists also reviewed and recorded information from the participant’s exercise log from the prior week and set new exercise goals for the following week. Gradual increases in the volume of physical activity were recommended over time at the discretion of the exercise physiologist. Participants who missed ≥1 of the 8 weekly phone calls were given the opportunity to reschedule 1 phone call.
Feasibility
Feasibility was assessed by the ability to recruit participants, number of participants who completed the 8-wk exercise intervention (defined as returning for the 8-wk study visit), number of 8 weekly exercise physiologist phone calls completed, time from baseline phone call to last weekly exercise physiologist phone call, and withdrawal rates. Reasons for study withdrawal were recorded.
Safety
Participants received verbal and written instructions throughout the study to stop exercising if they developed any symptoms such as chest pain, severe shortness of breath, lightheadedness, or dizziness. During each weekly phone call, the exercise physiologist asked each participant about any interim symptoms or adverse events. Any adverse events experienced during the study were recorded. Participants were withdrawn from the study if the study team felt it was no longer safe for the participant to continue exercise.
Acceptability
Acceptability was assessed using the same survey administered during our prior center-based exercise intervention.7 The survey was administered upon completion of the 8-wk intervention and consisted of the following questions (1 = strongly disagree to 5 = strongly agree): (1) I felt the exercise program was beneficial to my overall health, (2) I felt the exercise program was beneficial to my mental health, (3) I felt the exercise program was beneficial to my physical health, (4) I will continue to exercise regularly on my own after completing this program, and (5) I feel more confident about exercising on my own after completing this program. Participants were also asked open-ended questions about their experience with the 8-wk exercise intervention.
Exploratory Endpoints
Although the study was not powered to detect a change in outcomes, we examined the impact of the 8-wk exercise intervention on Physical Frailty Phenotype and Short Physical Performance Battery scores. Changes in weight, body composition, physical activity, self-reported energy/fatigue, self-reported physical health, and self-reported mental health from baseline to 8 wk were also assessed (Figure 1). Physical activity was measured using actigraphy. A triaxial accelerometer was placed on their upper extremity at both the baseline and 8-wk study visits. Participants wore the accelerometer for 7 d in a row before beginning the exercise intervention and again after completing the exercise intervention (Actigraph wGT3X-BT; Actigraph, Pensacola, Florida). The highest daily duration of sedentary, light, moderate, moderate to vigorous, vigorous, and very vigorous physical activity between the dates of accelerometer placement and removal was assessed. Self-reported physical and mental health was measured using the Kidney Disease Quality of Life Short Form (KDQOL-SF), version 1.3, by calculating the physical and mental component summary scores, respectively.13-15 KDQOL-SF scores range from 0 to 100, with higher scores indicating better quality of life. We also analyzed the change in energy/fatigue scores on the KDQOL-SF given that completion of our prior 8-wk center-based exercise intervention was associated with improvement in these scores.7 Body composition was measured in the subset of participants from the Mayo Clinic using bioelectrical impedance analysis (InBody 770; InBody, Cerritos, CA).
Sustainability
One month after completion of the 8-wk exercise intervention, participants received a survey via phone or mail asking about whether they were still exercising. Specifically, they were asked about the type, frequency, duration, and location of exercise they were engaged in 1 mo after study completion and any barriers to exercise they were experiencing. They were also asked if they felt the 8-wk exercise intervention they completed was beneficial to their physical health.
Statistical Analysis
We summarized categorical variables as counts and percentages and continuous variables as medians and interquartile ranges (IQRs). Baseline characteristics were compared in participants using the chi-square tests, F tests, and Kruskal-Wallis tests. Change in exploratory endpoints was analyzed using the McNemar test for categorical variables and the Wilcoxon signed-rank test for continuous variables. Chair stand time was set as 60 s in participants unable to complete the test. P values of ≤0.05 were considered statistically significant. Analyses were conducted with JMP (version 17.2.0, SAS Institute Inc).
RESULTS
Feasibility
A participant flow diagram is depicted in Figure 2. Of the 47 potentially eligible patients reached via a recruitment phone call, 28 (59.6%) declined study participation and 19 (40.4%) agreed to undergo screening. Reasons for declining study participation included patients lacking time or already exercising regularly. Patients who declined study participation did not differ from enrolled participants in terms of age (65.5 [IQR, 59–69] versus 64.0 y [IQR, 58–68], F27,14 = 1.13, P = 0.84) or White race (75.0% versus 73.3%, χ21 = 0.01, P = 0.91) but were slightly more likely to be women (57.1% versus 26.7%, χ21 = 3.65, P = 0.06). Among the 19 participants who agreed to undergo screening, 4 were found to be ineligible based on Physical Frailty Phenotype and Short Physical Performance Battery scores. Fifteen participants enrolled in the study. Of the 15 participants who were enrolled, 9 (60.0%) completed the 8-wk exercise intervention and 6 (40.0%) withdrew before completion. Reasons for withdrawal included intercurrent KT (n = 1), participant’s health problems (n = 3), and other issues (n = 2; please see Safety section).
FIGURE 2.
Participant flow diagram.
Participants collectively completed a total of 76 weekly exercise physiologist phone calls in addition to the baseline exercise physiologist phone calls. Of the 9 participants who completed the study and returned for the 8-wk study visit, 8 (88.9%) participated in ≥75.0% of the 8 weekly exercise physiologist phone calls. Specifically, 5 participants (55.6%) participated in all 8 weekly phone calls, 1 (11.1%) participated in 7 of 8 weekly phone calls, 2 (22.2%) participated in 6 of 8 weekly phone calls, and 1 (11.1%) participated in 4 of 8 weekly phone calls. The median time from the baseline phone call to the final weekly phone call was 9 wk (IQR, 8–9 wk). One participant took 18 wk to finish the 8-wk exercise intervention due to an intercurrent medical problem. Baseline frailty testing occurred a median of 8 d (IQR, 6–11 d) before initiation of the intervention, whereas completion frailty testing occurred a median of 7 d (IQR, 3–10 d) after completion of the intervention.
Patient Characteristics
Baseline characteristics of the study cohort are shown in Table 1. The median age of the 15 enrolled participants was 64 (IQR, 58–68) y, 73.3% were men, 73.3% were of White race, 53.3% were dialysis dependent (6 participants were receiving hemodialysis and 2 were receiving peritoneal dialysis), and 80.0% had diabetes. Ten participants were from the Mayo Clinic and 5 participants were from Baylor St. Luke’s Medical Center. The median baseline Physical Frailty Phenotype score was 2 (IQR, 1–2) and the median baseline Short Physical Performance Battery score was 9 (IQR, 8–10). The 5 participants who withdrew from the study for reasons other than KT reported significantly worse baseline exhaustion/fatigue and mental health than participants who completed the 8-wk exercise intervention (50.0 [IQR, 40.0–60.0] versus 20.0 [IQR, 15.0–37.5], P = 0.03 and 53.0 [IQR, 49.9–59.0] versus 50.8 [IQR, 40.2–51.0, P = 0.03, respectively; Table 1).
TABLE 1.
Baseline demographics
| Variable | Enrolled participants (N = 15), median (IQR) | Participants who completed the study (N = 9), median (IQR) |
Participants who withdrew from the study for reasons other than kidney transplantationa (N = 5), median (IQR) |
|---|---|---|---|
| Age, y | 64 (58–68) | 65 (58–68.5) | 64 (53.5–69) |
| Male | 11 (73.3%) | 6 (66.7%) | 4 (80.0%) |
| White race | 11 (73.3%) | 6 (66.7%) | 4 (80.0%) |
| Dialysis dependent | 8 (53.3%) | 4 (44.4%) | 4 (80.0%) |
| Diabetes | 12 (80.0%) | 7 (77.8%) | 4 (80.0%) |
| Never smoked | 10 (66.7%) | 5 (55.6%) | 4 (80.0%) |
| Body mass index, kg/m2 | 30.3 (27.7–37.6) | 29.9 (27.3–34.5) | 30.1 (28.0–35.5) |
| Physical Frailty Phenotype score | 2 (1–2) | 2 (0.5–2) | 2 (1.5–2) |
| Short Physical Performance Battery score | 9 (8–10) | 9 (8–10.5) | 9 (4–9.5) |
| Self-reported energy/fatigueb | 40.0 (20.0–60.0) | 50.0 (40.0–60.0) | 20.0 (15.0–37.5) |
| Self-reported physical healthb | 41.3 (31.3–44.7) | 43.2 (36.3–50.0) | 37.2 (31.8–40.3) |
| Self-reported mental healthb | 51.1 (48.1–53.2) | 53.0 (49.9–59.0) | 50.8 (40.2–51.0) |
aThe participant who withdrew from the study due to intercurrent kidney transplantation was excluded from these comparisons.
bAssessed via KDQOL-SF score range from 0 to 100, with higher scores indicating better quality of life.
IQR, interquartile range; KDQOL-SF, Kidney Disease Quality of Life Short Form.
Safety
No unanticipated adverse events occurred. Three participants experienced anticipated adverse events that were possibly related to the study. Specifically, 1 participant experienced transient musculoskeletal pain but completed the study, 1 participant experienced persistent musculoskeletal pain and was withdrawn from the study, and 1 participant experienced shortness of breath and was withdrawn from the study.
Acceptability
On completion of the 8-wk exercise intervention, 77.8% of participants (n = 7/9) reported being willing to complete the intervention again. Participants strongly agreed that the 8-wk exercise intervention was beneficial to their overall health (median score 5 [IQR, 4–5]), their mental health (median score 5 [IQR, 3–5]), and their physical health (median score 5 [IQR, 4.5–5]). Furthermore, participants strongly agreed that they would continue to exercise following intervention completion (median score 5 [IQR, 4–5]) and strongly agreed that they felt more confident about exercise following intervention completion (median score 5 [IQR, 3.5–5]). When asked about what they did not like about the exercise program or what they would change, several participants commented on the “paperwork” and “adding more work,” presumably related to the article logs on which the participants were asked to record their daily physical activity. Participant comments regarding their exercise goals and opinions regarding the 8-wk exercise intervention on intervention completion are displayed in Table 2.
TABLE 2.
Participant feedback regarding the 8-wk exercise intervention
| 8-wk study visit | |
|---|---|
| Survey question | Participant feedback |
| What were your goals for participation in the exercise program? | • [To) feel better. • “Strength.” • Increase intensity [of exercise]. • Staying accountable. • Create a routine. • Staying active. • Better my health. • To be stronger and able to exercise with ease. |
| What did you like about the exercise program? | • [It kept me] active. • Pedal exerciser. • Motivation. • Accountability. • Feeling better. • [It helped] me better my health. |
| What didn’t you like about the exercise program? Would you change anything? | • Paperwork.a • Adding more work.a • Accountability. • Missing days. • Resistance bands. |
| 1 mo postintervention | |
| Survey question | Participant feedback |
| If you felt the exercise program you completed at Mayo Clinic or Baylor College of Medicine was beneficial to your physical health, why was it beneficial? | • Lost weight. • Kept [me] moving. • It gives me better health and makes me strong. • Helps with mobility. • Improved activity… • Motivated. Accountable. • …feeling stronger… • Motivated me to do other workouts. • Makes me feel more energetic; helps me move way better. |
aPresumably related to the article logs on which the participants were asked to record their daily physical activity.
Exploratory Endpoints
Change in exploratory endpoints following completion of the 8-wk exercise intervention compared with baseline are displayed in Table 3. No significant change in Physical Frailty Phenotype or Short Physical Performance Battery scores was observed, although there was a trend toward improved grip strength (P = 0.07). No significant change in weight; duration of daily sedentary, light, moderate, moderate to vigorous, vigorous, or very vigorous physical activity; self-reported physical or mental health; self-reported energy/fatigue; or percent body fat was observed.
TABLE 3.
Relationship between 8-wk exercise intervention and exploratory endpoints
| Outcome | (N = 15), median (IQR) | 8 wk (N = 9), median (IQR) |
Median difference, median (IQR) |
P a |
|---|---|---|---|---|
| Physical Frailty Phenotype score | 2 (1–2) | 1 (0.5–1.5) | 0 (–1 to 0) | 0.37 |
| Grip strength, kg | 27.7 (21.1–31.6) | 29.9 (22.0–37.9) | 2.8 (0.2–6.3) | 0.07 |
| Short Physical Performance Battery score | 9 (8–10) | 8 (7.5–10) | –1 (–2 to 1.5) | 0.73 |
| Gait speed, m/s | 1.1 (0.9–1.3) | 1.0 (0.9–1.3) | –0.1 (–0.3 to 0.2) | 0.65 |
| Weight, kg | 89.5 (83.7–103.5) | 92.6 (80.2–100.9) | –1.1 (–2.1 to 0.2) | 0.15 |
| Moderate to vigorous physical activity per day, h | 1.6 (1.1–2.9)b | 1.7 (1.5–2.7) | –0.4 (–0.1 to 0.4) | 0.55 |
| Self-reported energy/fatiguec | 40.0 (20.0–60.0) | 70.0 (27.5–75.0) | 10.0 (–5.0 to 20.0) | 0.31 |
| Self-reported physical healthc | 41.3 (31.3–44.7) | 46.4 (42.9–50.5)d | –1.8 (–6.1 to 5.8) | 0.95 |
| Self-reported mental healthc | 51.1 (48.2–53.2) | 56.1 (50.1–57.7)d | 1.7 (–9.4 to 8.4) | 0.95 |
| Percent body fat | 35.0 (18.6–39.4)e | 36.1 (14.4–38.3)f | 0.9 (0–1.3) | 0.31 |
aEight week compared with baseline using the Wilcoxon signed-rank test for continuous variables and the McNemar test for categorical variables.
bN = 14.
cAssessed via KDQOL-SF.
dN = 8.
eN = 9.
fN = 7.
IQR, interquartile range; KDQOL-SF, Kidney Disease Quality of Life Short Form.
Sustainability
One month after completion of the 8-wk exercise intervention, 100% of participants (n = 9/9) reported continuing to exercise 3–5 d per week. Types of reported exercise included walking, using a stationary bicycle, and swimming. Participants reported exercising at home, outside, and at the gym. All participants reported that the intervention was beneficial to their physical health. Participant comments regarding the 8-wk exercise intervention 1 mo after completion are displayed in Table 2.
DISCUSSION
In this study, we adapted a previously developed 8-wk center-based exercise intervention for home-based delivery in KT candidates.7 We found that the home-based exercise intervention was feasible. Specifically, 60.0% of participants completed the intervention, of whom 88.9% completed ≥75.0% of the 8 weekly exercise physiologist phone calls. The intervention was safe, with no unanticipated adverse events. The intervention was acceptable to participants, with most strongly agreeing that the intervention was beneficial to their overall health, and all of the participants reported sustained exercise 1 mo after intervention completion. Although our study was not designed to examine intervention efficacy, it provides important preliminary data for future randomized trials examining the impact on frailty, health-related quality of life, and body composition.
Multiple facets of our home-based intervention make it a promising prehabilitation intervention for KT candidates. First, our intervention was “individualized” and “progressive” to meet the needs of patients with varying levels of physical function. Second, it involved “standardized” physical activity guidelines from the American Heart Association and the American Association of Cardiovascular and Pulmonary Rehabilitation.12 Third, it was delivered by exercise physiologists who are “widely available” at cardiac rehabilitation centers across the United States. Fourth, it was delivered to participants from both Minnesota and Texas and can thus meet the needs of KT candidates “geographically dispersed” from their transplant centers. Fifth, it was conducted at home to provide “access to exercise in participants without transportation.” Finally, it provided participants with the opportunity for “sustained” exercise after study completion; participants were given exercise equipment to use at home and taught how to use the equipment.
Although our intervention has multiple strengths, our study highlights several areas for improvement. Our study demonstrates that engaging patients with renal failure, especially female patients and those with worse self-reported energy/fatigue and mental health, in exercise programs can be challenging. Our withdrawal rate of 40.0% was higher than the withdrawal rate associated with our prior center-based intervention (29.6%).7 These findings suggest that KT candidates may benefit from preintervention counseling to promote participation and enhance engagement. Another area for intervention improvement includes the management of anticipated adverse events. Sedentary lifestyles and multiple comorbidities predispose KT candidates to anticipated adverse events such as musculoskeletal pain and shortness of breath. Physical therapists or cardiologists may need to be available for study participants who develop anticipated adverse events to help them safely and confidently continue to exercise. Finally, future research studies should attempt to minimize the use of exercise logs to avoid overburdening participants, and future clinical programs should consider omitting them completely.
Our study has important limitations. Our cohort involved predominately White participants fluent in English. Thus, our study findings may not generalize to other patient groups. Future studies should attempt to engage underrepresented communities via expansion to other transplant centers, oversampling, and the development of multilingual research documents. Our intervention involved only exercise (“unimodal”); future iterations of our intervention may benefit from the incorporation of components such as counseling and nutritional education (“multimodal”). Limited data regarding intervention acceptability and sustainability were collected 1 mo after completion of the intervention. Future studies would benefit from collecting more detailed participant feedback regarding barriers and facilitators to continued exercise for a longer period of time following study completion, including types of exercise participants find most useful or most difficult to sustain. Furthermore, future studies should collect feedback from patients about why they declined study participation or withdrew from the study and whether they would consider similar studies in the future. Our study was unrandomized and small; future studies should be randomized and powered to detect efficacy in different subgroups, including patients on dialysis compared with patients not on dialysis. Finally, future studies should compare the efficacy and cost-effectiveness of center- versus home-based interventions.
In conclusion, we demonstrate that an individualized, standardized 8-wk home-based exercise intervention delivered by exercise physiologists via phone appears to be feasible, safe, and acceptable in KT candidates from 2 different transplant centers. Future studies will benefit from focusing on improving participant engagement in the intervention and incorporating strategies to deal with anticipated adverse events. This study provides important preliminary data for a future randomized controlled trial examining the efficacy of prehabilitation in KT candidates.
Footnotes
E.C.L. is supported by the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health (award number DK 123313).
The authors declare no conflicts of interest.
E.C.L. participated in research design, writing the article, performing the research, and data analysis. A.R.B. participated in research design. A.C.D.-V.M., C.L.M., C.A.R., R.M.S., A.D.W., and B.V.M. participated in performing the research. L.A.D. and N.G.C. participated in writing of the article. C.C.K. participated in research design, writing the article, and data analysis.
Clinical Trial NCT04745169.
Contributor Information
Amanda R. Bonikowske, Email: bonikowske.amanda@mayo.edu.
Ashley C. David-Van Meter, Email: david.ashley@mayo.edu.
Cortney L. Munson, Email: munson.cortney@mayo.edu.
Callie A. Roschen, Email: roschen.callie@mayo.edu.
Rosalyn M. Salstrand, Email: salstrand.rosalyn@mayo.edu.
Anne D. Wolter, Email: wolter.anne@mayo.edu.
LaShara A. Davis, Email: ladavis@houstonmethodist.org.
Namkee G. Choi, Email: nchoi@austin.utexas.edu.
Cassie C. Kennedy, Email: kennedy.cassie@mayo.edu.
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