RESUMEN
BACKGROUND: Posttransplant metabolic syndrome (PTMS) is a common contributor to morbidity and mortality among solid organ transplant recipients in the late posttransplant period (≥1 year). Patients diagnosed with PTMS are at a higher risk of cardiovascular disease and frequently experience decreased physical function and health-related quality of life (HRQL). Studies in the early posttransplant period (<1 year) have shown the benefits of facility-based exercise training on physical function and HRQL, but have not evaluated the effects on metabolic risk factors. It remains unclear whether home-based exercise programs are feasible and can be delivered at a sufficient exercise dose to have effects on PTMS. This protocol outlines the methodology of a randomized controlled trial of a partly supervised home-based exercise program in lung transplant (LTx) and orthotopic liver transplant (OLT) recipients. OBJECTIVE: This study aims to evaluate the feasibility (ie, recruitment rate, program adherence, attrition, safety, and participant satisfaction) of a 12-week individualized, home-based aerobic and resistance training program in LTx and OLT recipients initiated 12 to 18 months after transplantation, and to assess estimates of intervention efficacy on metabolic risk factors, exercise self-efficacy, and HRQL. METHODS: In total, 20 LTx and 20 OLT recipients with ≥2 cardiometabolic risk factors at 12 to 18 months after transplantation will be randomized to an intervention (home-based exercise training) or control group. The intervention group will receive an individualized exercise prescription comprising aerobic and resistance training, 3 to 5 times a week for 12 weeks. Participants will meet on a weekly basis (via videoconference) with a qualified exercise professional who will supervise exercise progression, provide support, and support exercise self-efficacy. Participants in both study groups will receive a counseling session on healthy eating with a dietitian at the beginning of the intervention. For the primary aim, feasibility will be assessed through recruitment rate, program adherence, satisfaction, attrition, and safety parameters. Secondary outcomes will be measured at baseline and 12 weeks, including assessments of metabolic risk factors (ie, insulin resistance, abdominal obesity, blood pressure, and cholesterol), HRQL, and exercise self-efficacy. Descriptive statistics will be used to summarize program feasibility and effect estimates (means and 95% CIs) for sample size calculations in future trials. RESULTS: Enrollment started in July 2021. It is estimated that the study period will be 18 months, with data collection to be completed by December 2022. CONCLUSIONS: A partly supervised home-based, individually tailored exercise program that promotes aerobic and resistance training and exercise self-efficacy may be an important intervention for improving the metabolic profile of LTx and OLT recipients with cardiometabolic risk factors. Thus, characterizing the feasibility and effect estimates of home-based exercise constitutes the first step in developing future clinical trials designed to reduce the high morbidity associated with PTMS. TRIAL REGISTRATION: ClinicalTrials.gov NCT04965142; https://clinicaltrials.gov/ct2/show/NCT04965142. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/35700.
RESUMEN
BACKGROUND: Malnutrition in lung transplant (LTx) candidates is an important risk factor for adverse outcomes. We sought to evaluate the Nutritional Risk Index (NRI) in LTx candidates, a validated measure of malnutrition risk in chronic disease. We aimed to characterize malnutrition risk using NRI, evaluate change in body weight between nutritional risk groups, and assess association of malnutrition risk with pretransplant and posttransplant outcomes. METHODS: Retrospective, single-center cohort study of LTx candidates (2014-2015) evaluated by a dietitian before listing. Nutritional parameters, weight change pretransplant and posttransplant, and clinical outcomes were abstracted up to 1-year posttransplant. NRI was calculated as follows: (1.519 × albumin) + (41.7 × current weight/ideal weight) with high malnutrition risk defined as the lowest quartile of NRI for cystic fibrosis (CF) and non-CF patients. RESULTS: The cohort comprises 247 LTx candidates (57% male; median age 59 y; non-CF 88%). Non-CF candidates had a greater mean NRI compared with CF patients (109 ± 11 versus 95 ± 12; P < 0.0001). 86% with high malnutrition risk maintained/gained weight (≥5%) pretransplant. In 196 LTx recipients, malnutrition risk was not associated with hospital stay, discharge disposition, or 1-year mortality. The median percent weight gain for LTx recipients in the first year was 10.5% (4.0-20.1), with high malnutrition risk recipients having comparable or greater weight gain to the low-risk group (mean difference for non CF: 6.8%; P = 0.02 and CF: -3.8%; P = 0.65). CONCLUSIONS: Malnutrition risk assessed with NRI was not prognostic of posttransplant outcomes in this retrospective cohort. LTx candidates with high malnutrition risk were able to maintain their weight pretransplant and demonstrated considerable weight gain in the first-year posttransplant.
