Candidacy for Lung Transplant and Lung Allocation

Lung Allocation Score Exceptions in Persons with Cystic Fibrosis Undergoing Lung Transplant

Rationale: Lung transplantation can extend the lives of individuals with advanced cystic fibrosis (CF). Until March 2023, the Lung Allocation Score (LAS) was used in the United States to determine transplant priority. Certain clinical events or attributes ("risk events") that are not included in the LAS (e.g., massive hemoptysis) are relatively common and prognostically important in CF and may prompt an exception request to increase priority for donor lungs. The new Lung Composite Allocation Score (CAS) also allows for exceptions based on the same principles. Objectives: To evaluate the frequency of LAS exceptions in persons with CF (PwCFs) listed for lung transplantation and assess whether LAS exceptions are associated with improved waitlist outcomes for PwCFs compared with similarly "at-risk" individuals without LAS exceptions. Methods: A merged dataset combining data from the CF Foundation Patient Registry and the Organ Procurement and Transplantation Network (2005-2019) was used to identify PwCFs listed for lung transplantation. We compared waitlist outcomes between PwCFs with a LAS exception versus those without an exception despite having a risk event. Risk events were defined as an episode of massive hemoptysis, pneumothorax, at least three moderate/severe pulmonary exacerbations, and/or a decrease in forced expiratory volume in 1 second by ⩾30% predicted (absolute) in the prior 12 months. Analyses were performed using competing risk regression with time to transplantation as the primary outcome and death without a transplant as a competing risk. Results: Of 3,538 listings from 3,309 candidates, 2% of listings (n = 81) had at least one exception. Candidates with an exception and those with a risk event but no exception received lung transplants more slowly than people without an exception or risk event (subdistribution hazard ratio [95% confidence interval]: LAS exception cohort, 0.66 [0.52-0.85]; risk event cohort without exceptions, 0.79 [0.72-0.86]). There was no difference between those with LAS exceptions and those at risk without LAS exceptions: subdistribution hazard ratio, 0.84 (0.66-1.08). Conclusions: LAS exceptions are rare in PwCFs listed for lung transplantation. LAS exceptions resulted in a similar time to transplantation for PwCFs compared with similarly at-risk individuals. As we enter the CAS era, these LAS-based results are pertinent to improve risk stratification among PwCFs being considered for lung transplantation.

Excluding patients from transplant due to social support: Results from a national survey of transplant providers

Social support is used to determine transplant eligibility despite lack of an evidence base and vague regulatory guidance. It is unknown how many patients are disqualified from transplantation due to inadequate support, and whether providers feel confident using these subjective criteria to determine eligibility. Transplant providers (n = 551) from 202 centers estimated that, on average, 9.6% (standard deviation = 9.4) of patients evaluated in the prior year were excluded due to inadequate support. This varied significantly by United Network for Organ Sharing region (7.6%-12.2%), and by center (21.7% among top quartile). Significantly more providers used social support in listing decisions than believed it ought to be used (86.3% vs 67.6%). Nearly 25% believed that using social support in listing determinations was unfair or were unsure; 67.3% felt it disproportionately impacted patients of low socioeconomic status. Overall, 42.4% were only somewhat or not at all confident using social support to determine transplant suitability. Compared to surgical/medical transplant providers, psychosocial providers had 2.13 greater odds of supporting the criteria (P = .03). Furthermore, 69.2% supported revised guidelines for use of social support in listing decisions. Social support criteria should be reconsidered in light of the limited evidence, potential for disparities, practice variation, low provider confidence, and desire for revised guidelines.

Is social support associated with post-transplant medication adherence and outcomes? A systematic review and meta-analysis

Although social support is used to determine transplant eligibility, the relationship between social support, medication adherence, and survival among transplant recipients remains unclear. We estimated the relationship between social support and post-transplant medication adherence and outcomes using 10 electronic databases from inception to January 2016. Study quality was assessed and all review stages were conducted independently by 2 reviewers. Systematic review and meta-analysis were conducted. Thirty-two studies (9102 participants) met inclusion criteria: 21 assessed medication adherence (5197 participants), and 13 assessed clinical outcomes (3905 participants). Among high quality studies, neither social support nor marital status was predictive of medication adherence or post-transplant outcomes. Social support was not associated with medication adherence. It was associated with superior post-transplant outcomes, but the relationship was not significant among high quality studies. Compared to unmarried recipients, married recipients were more likely to adhere to medication post-transplant, but this relationship was not significant among high quality studies. Marital status was not significantly associated with transplant success. Social support is weakly and inconsistently associated with post-transplant adherence and outcomes. Larger prospective studies using consistent and validated measures are needed to justify the use of inadequate social support as a contraindication to transplantation.

Twenty-years of lung transplantation in Taiwan: Effects of cumulative institutional experience on early outcomes

BACKGROUND/PURPOSE

Lung transplantation in Taiwan began in 1991, but the experience was limited and diverse in the early years. We examined the cumulative institutional experience of the largest lung transplant cohort in Taiwan.

METHODS

A retrospective review of lung transplantations performed at a single institution from December 1995 through August 2016 was conducted. For comparative purposes, the cohort was divided into halves, with an early group (undergoing lung transplantation in the first decade) vs a late group (undergoing lung transplantation in the second decade). Standardized donor selection, organ procurement, and preservation protocols for brain-dead donors were applied. The outcomes measured were 30-day mortality and actuarial survival using the Kaplan-Meier method.

RESULTS

The cohort included 50 recipients in the early group and 42 recipients in the late group. Compared with the early group, recipients in the late group were significantly older (38.8 ± 11.6 vs 44.8 ± 13.4 years, p = 0.024) and more of them required mechanical ventilation before transplant (26.0% vs 66.7%, p < 0.001). There were more female donors (12.0% vs 33.3%, p = 0.021) and gender-matched donors (34.0% vs 61.9%, p = 0.012) in the late group. A total of 87 recipients (94.6%) had cardiopulmonary bypass (CPB) or extracorporeal membrane oxygenation (ECMO) support during transplant, and CPB was used significantly less in the late group. Graft procedures (14.0% vs 47.6%, p < 0.001), delayed chest closure (0% vs 21.4%, p < 0.001), and early tracheostomy (24.0% vs 52.4%, p = 0.005) were performed more in the late group. The durations of hospital and ICU stays were comparable in both groups, but the 30-day mortality was significantly lower in the late group (30.0% vs 2.4%, p = 0.001).

CONCLUSION

Although the results were undesirable in the first decade of the transplant program, the cumulative institutional experience led to significantly improved outcomes in the second decade of the transplant program.