Factors affecting discharge destination following lung transplantation

Construct and Predictive Validity of Sarcopenia in Lung Transplant Candidates

Rationale: Sarcopenia is associated with disability and death. The optimal definition and clinical relevance of sarcopenia in lung transplantation remain unknown. Objectives: To assess the construct and predictive validity of sarcopenia definitions in lung transplant candidates. Methods: In a multicenter prospective cohort of 424 lung transplant candidates, we evaluated limited (muscle mass only) and expanded (muscle mass and quality) sarcopenia definitions from the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), the Foundation for the National Institutes of Health (FNIH), and a cohort-specific distribution-based lowest quartile definition. We assessed construct validity using associations with conceptually related factors. We evaluated the relationship between sarcopenia and frailty using generalized additive models. We also evaluated associations between sarcopenia definitions and key pretransplant outcomes, including disability (quantified by the Lung Transplant Valued Life Activities scale [range, 0-3; higher scores = worse disability; minimally important difference, 0.3]) and waitlist delisting/death, by multivariate linear and Cox regression, respectively. Results: Sarcopenia prevalence ranged from 6% to13% by definition used. The limited EWGSOP2 definition demonstrated the highest construct validity, followed by the expanded EWGSOP2 definition and both limited and expanded FNIH and lowest quartile definitions. Sarcopenia exhibited a linear association with the risk of frailty. The EWGSOP2 and expanded lowest quartile definitions were associated with disability, ranging from 0.20 to 0.25 higher Lung Transplant Valued Life Activities scores. Sarcopenia was associated with increased risk of waitlist delisting or death by the limited and expanded lowest quartile definitions (hazard ratio [HR], 3.8; 95% confidence interval [CI], 1.4-9.9 and HR, 3.5; 95% CI, 1.1-11.0, respectively) and the EWGSOP2 limited definition (HR, 2.8; 95% CI, 0.9-8.6) but not with the three other candidate definitions. Conclusions: The prevalence and validity of sarcopenia vary by definition; the EWGSOP2 limited definition exhibited the broadest validity in lung transplant candidates. The linear relationship between low muscle mass and frailty highlights sarcopenia's contribution to frailty and also questions the clinical utility of a sarcopenia cut-point in advanced lung disease. The associations between sarcopenia and important pretransplant outcomes support further investigation into using body composition for candidate risk stratification.

Selection Criteria for Lung Transplantation: Controversies and New Developments

Lung transplantation is an accepted therapeutic option for end-stage lung diseases. The imbalance between limited availability and vast need of donor organs necessitates careful selection of recipient candidates, ensuring the best possible utilization of the scarce resource of organs. Nonetheless, possible lung transplant candidates who could experience a meaningful improvement in survival and quality of life should not be excluded solely based on the complexity of their case. In this review, controversial issues or difficult limitations for lung transplantation, and new developments in recipient selection criteria, are discussed, which may help broaden recipient eligibility for lung transplantation without compromising long-term outcomes.

Impaired cardiac autonomic response in lung transplant patients: A retrospective cohort study

BACKGROUND

Cardiac autonomic dysfunction (AD) is associated with adverse prognosis in lung disease; however, its implications in lung transplantation have not been previously described. This study evaluated the prevalence of AD in lung transplant (LTx) candidates, its determinants, prognostic implications, and prevalence post-transplant.

METHODS

Retrospective one-year study of 103 LTx candidates with AD assessed using heart rate (HR) from the six-minute walk test (6MWT). Impaired chronotropic response index (CRI) was defined as <80% age-adjusted HR during 6MWT. Abnormal HR recovery (HRR) was categorized as reduction in HR ≤ 12 beats/minute after the first minute of 6MWT cessation.

RESULTS

Abnormal CRI and HRR were observed in 94% and 76% of patients, respectively. A lower CRI was associated with obstructive lung disease and lower estimated aerobic capacity. CRI was independently associated with 6MW distance [12 m per 10% CRI, P = 0.03], but not with post-transplant cardiovascular events, hospital stay, or one-year mortality. At 3 months post-transplant, no improvement was observed in CRI (99%, n = 66/67, P = 0.25) or HRR (88%, n = 36/41, P = 0.12).

CONCLUSION

Cardiac AD was prevalent in LTx candidates and recipients, with chronotropic incompetence a modest contributor to exercise intolerance pretransplant. Further study may help determine whether direct autonomic measures such as HR variability may be more prognostic of LTx outcomes.

In-hospital and subsequent mortality among lung transplant recipients with a prolonged initial hospitalization

The care of lung transplant recipients with prolonged index hospitalizations can be ethically complex, with conflicts arising over whether the expected outcomes justify ongoing intensive interventions. There are limited data to guide these conversations. The objective of this study was to evaluate survival to discharge for lung transplant recipients based on length of stay (LOS). This was a retrospective cohort study of adult lung transplant recipients in the Scientific Registry of Transplant Recipients. For each day of the index hospitalization the mortality rate among patients who survived to that length of stay or longer was calculated. Post-discharge survival was compared in those with and without a prolonged hospitalization (defined as the 97th percentile [>90 days]). Among the 19 250 included recipients, the index hospitalization mortality was 5.4%. Posttransplant stroke and need for dialysis were the strongest predictors of index hospitalization mortality. No individual or combination of available risk factors, however, was associated with inpatient mortality consistently above 50%. Recipients with >90 day index hospitalization had a 28.8% subsequent inpatient mortality. Their 1, 3 and 5 year survival following discharge was 53%, 26%, and 16%. These data provide additional context to goals of care conversations for transplant recipients with prolonged index hospitalizations.

Predictors of Long-Term Exercise Capacity in Patients Who Have Had Lung Transplantation

INTRODUCTION

Six-minute walk distance (6MWD) is a widely used surrogate for exercise capacity in patients both pre- and post-lung transplant. Multiple factors have been suggested to influence exercise capacity.

RESEARCH QUESTIONS

This study sought to determine the change in exercise capacity over time and factors that influence long-term exercise capacity.

DESIGN

Data were collected prospectively on lung transplant recipients from 1 center. The 6MWD was measured preoperatively and at the 6- and 12-month clinic visits postoperatively. The Enright equation was used to calculate patients' percentage predicted 6MWD. The change in 6MWD over time was calculated, and multiple factors affecting 6MWD were analyzed, including predictors of 6MWD at 6 and 12 months posttransplant.

RESULTS

Sixty lung transplant recipients were enrolled. Significant improvement in 6MWD was found between pretransplant and hospital discharge and between hospital discharge and 6 months posttransplant. The percentage predicted 6MWD improved significantly from pretransplant to 6 months and to 12 months posttransplant. Factors associated with 6MWD were sex, diagnosis, graft type, and age. Factors predicting long-term exercise capacity included 6MWD at referral, pretransplant, and hospital discharge; pulmonary diagnosis; and type of transplant.

CONCLUSION

The 6MWD provided useful information about patients' exercise capacity during phases of lung transplantation. The percentage predicted for each patient was found to be a more valuable measure than absolute 6MWD. Intensive, individualized training posttransplant is essential to optimize exercise capacity for this population.

Recent alcohol use prolongs hospital length of stay following lung transplant

Little is known about the alcohol habits of people with advanced lung disease. Following lung transplantation, patients are asked to abstain from or minimize alcohol use. The aim of this investigation was to assess alcohol use in a cohort of patients with advanced lung disease undergoing evaluation for lung transplant. This is a prospective observational investigation comparing patient self-report of alcohol use with their responses on the Alcohol Use Disorders Identification Test (AUDIT), and alcohol biomarkers collected at the time of transplant. There were 86 included in the cohort, 34% currently using alcohol, 13% had AUDIT scores >3, and 10% had positive results for alcohol biomarkers at the time of transplantation. Patients with evidence of recent alcohol use prior to lung transplant surgery had a 1.5-fold increase in hospital length of stay following lung transplant (P = .028), spent 3 times as long on mechanical ventilation after transplant, and required intensive care unit monitoring nearly 3 times longer than those without recent alcohol use (P = .008). There were no differences in primary graft dysfunction, although several patients with recent alcohol use had post-transplant atrial arrhythmias, acute kidney injury, and acute cellular rejection. Abstaining from alcohol use may optimize outcomes following lung transplant.

Lung transplantation in elderly patients

Consensus statements on the selection of lung transplant candidates have consistently identified older age as a relative contraindication to transplantation. A combination of population-level demographic changes, revision of the lung allocation score (LAS), and clearer data on outcomes in elderly transplant recipients has, however, driven a steady increase in the threshold at which age is taken into consideration. This article reviews the current state of lung transplantation in elderly patients with an emphasis on the factors that have increased lung transplantation in older age groups, their expected outcomes including survival and health-related quality of life, and the factors that go in to appropriate candidate and procedure selection in this population.

Thoracic muscle cross-sectional area is associated with hospital length of stay post lung transplantation: a retrospective cohort study

Low muscle mass is common in lung transplant (LTx) candidates; however, the clinical implications have not been well described. The study aims were to compare skeletal muscle mass in LTx candidates with controls using thoracic muscle cross-sectional area (CSA) from computed tomography and assess the association with pre- and post-transplant clinical outcomes. This was a retrospective, single-center cohort study of 527 LTx candidates [median age: 55 IQR (42-62) years; 54% male]. Thoracic muscle CSA was compared to an age- and sex-matched control group. Associations between muscle CSA and pre-transplant six-minute walk distance (6MWD), health-related quality of life (HRQL), delisting/mortality, and post-transplant hospital outcomes and one-year mortality were evaluated using multivariable regression analysis. Muscle CSA for LTx candidates was about 10% lower than controls (n = 38). Muscle CSA was associated with pre-transplant 6MWD, but not HRQL, delisting or pre- or post-transplant mortality. Muscle CSA (per 10 cm² difference) was associated with shorter hospital stay [0.7 median days 95% CI (0.2-1.3)], independent of 6MWD. In conclusion, thoracic muscle CSA is a simple, readily available estimate of skeletal muscle mass predictive of hospital length of stay, but further study is needed to evaluate the relative contribution of muscle mass versus functional deficits in LTx candidates.

Physical rehabilitation for lung transplant candidates and recipients: An evidence-informed clinical approach

Physical rehabilitation of lung transplant candidates and recipients plays an important in optimizing physical function prior to transplant and facilitating recovery of function post-transplant. As medical and surgical interventions in lung transplantation have evolved over time, there has been a demographic shift of individuals undergoing lung transplantation including older individuals, those with multiple co-morbidites, and candidates with respiratory failure requiring bridging to transplantation. These changes have an impact on the rehabilitation needs of lung transplant candidates and recipients. This review provides a practical approach to rehabilitation based on research and clinical practice at our transplant centre. It focuses on functional assessment and exercise prescription during an uncomplicated and complicated clinical course in the pre-transplant, early and late post-transplant periods. The target audience includes clinicians involved in pre- and post-transplant patient care and rehabilitation researchers.