Adult Lung Transplant Candidates Research Articles

Unveiling Hidden Disparities: Evaluating US Multiple Listing Practices in Lung Transplantation

BackgroundMultiple listing (ML) is a practice utilized to increase the potential for transplant but is controversial due to concerns that it disproportionately benefits patients with greater access to healthcare resources. Research QuestionIs there disparity in ML practices based on social deprivation in the United States and does ML lead to quicker time to transplant? Study design and methodsA retrospective cohort study of adult (>18 years old) lung transplant candidates listed for transplant (2005-2018) was conducted. Exclusion criteria included heart only or heart and lung transplant and patients relisted during the observation period. Data were obtained from the UNOS Standard Transplant Analysis and Research File. The first exposure of interest was social deprivation index (SDI) with a primary outcome of ML status, to assess disparities between ML and SL participants. The second exposure of interest was ML status with a primary outcome of time to transplant, to assess whether implementation of ML leads to quicker time to transplant. Results35,890 subjects were included in the final analysis, of whom 791 (2.2%) were ML and 35,099 (97.8%) were SL. ML participants had lower median level of social deprivation (5 units, more often female (60.0% vs 42.3%), and had lower median LAS (35.3 vs 37.3). ML patients were more likely to be transplanted compared to SL patients (OR=1.42, 95%CI [1.17-1.73]), but there was a significantly quicker time to transplant only for whom ML was early (within 6 months of initial listing) (sHR=1.17, 95%CI [1.04-1.32]). InterpretationML is an uncommon practice with disparities existing between ML and SL patients on the basis of several factors including social deprivation. ML patients are more likely to be transplanted, but only if they ML early in their transplant candidacy. With changing allocation guidelines, it is yet to be seen how ML will change with the implementation of continuous distribution.

To decline or not to decline: Consequences of decision-making regarding lung offers from donors with hepatitis C

ObjectiveLung transplants from donors with hepatitis C (HCV D+) have excellent outcomes, but these organs continue to be declined. We evaluated whether (1) being listed to consider and (2) accepting versus declining HCV D+ offers provided a survival benefit to lung transplant candidates. MethodsUsing the Scientific Registry of Transplant Recipients, we identified all adult (≥18 years) lung transplant candidates 2016-2021 and compared waitlist mortality between those willing versus not willing to consider HCV D+ offers using competing risk regression. We identified all candidates offered an HCV D+ lung that was later accepted and followed them from offer decision until death or end-of-study. We estimated adjusted mortality risk of accepting versus declining an HCV D+ lung offer using propensity-weighted Cox regression. ResultsFrom 2016 to 2021, we identified 21,007 lung transplant candidates, 33.8% of whom were willing to consider HCV D+ offers. Candidates willing to consider HCV D+ offers had a 17% lower risk of waitlist mortality (subhazard ratio, 0.83; 95% confidence interval, 0.75-0.91, P < .001). Over the same period, 665 HCV D+ lung offers were accepted after being declined a total of 2562 times. HCV D+ offer acceptance versus decline was associated with a 20% lower risk of mortality (adjusted hazard ratio, 0.80; 95% confidence interval, 0.66-0.96, P = .02). ConclusionsConsidering HCV D+ lung offers was associated with a 17% lower risk of waitlist mortality, whereas accepting versus declining an HCV D+ lung offer was associated with a 20% lower risk of mortality. Centers and candidates should consider accepting suitable HCV D+ lung offers to optimize outcomes.

Racial Disparities in Waiting List Outcomes of Patients Listed for Lung Transplantation

BackgroundThe Lung Allocation Score, implemented in 2005, prioritized lung transplant candidates by medical urgency rather than waiting list time and was expected to improve racial disparities in transplant allocation. We evaluated whether racial disparities in lung transplant persisted after 2005. MethodsWe identified all wait-listed adult lung transplant candidates in the United States from 2005 through 2021 using the Scientific Registry of Transplant Recipients. We evaluated the association between race and receipt of a transplant by using a multivariable competing risk regression model adjusted for demographics, socioeconomic status, Lung Allocation Score, clinical measures, and time. We evaluated interactions between race and age, sex, socioeconomic status, and Lung Allocation Score. ResultsWe identified 33,158 candidates on the lung transplant waiting list between 2005 and 2021: 27,074 White (82%), 3350 African American (10%), and 2734 Hispanic (8%). White candidates were older, had higher education levels, and had lower Lung Allocation Scores (P < .001). After multivariable adjustment, African American and Hispanic candidates were less likely to receive lung transplants than White candidates (African American: adjusted subhazard ratio, 0.86; 95% CI, 0.82-0.91; Hispanic: adjusted subhazard ratio, 0.82; 95% CI, 0.78-0.87). Lung transplant was significantly less common among Hispanic candidates aged >65 years (P = .003) and non-White candidates from higher-poverty communities (African-American: P = .013; Hispanic: P =.0036). ConclusionsDespite implementation of the Lung Allocation Score, racial disparities persisted for wait-listed African American and Hispanic lung transplant candidates and differed by age and poverty status. Targeted interventions are needed to ensure equitable access to this life-saving intervention.

New OPTN/UNOS data demonstrates higher than previously reported waitlist mortality for lung transplant candidates supported with ECMO

Use of extracorporeal membrane oxygenation (ECMO) is not currently incorporated into US allocation models due to the historical lack of complete data in the national US registry which changed in 2016 to include ECMO at the time of waitlist removal and more granular timing and configuration data. We studied adult lung transplant candidates from 01 May 2016 to 01 June 2020 with data abstracted from multiple sources in the US Scientific Registry of Transplant Recipients. Waitlist analyses included cumulative incidence functions and Cox proportional hazards (PH) models considering ECMO as a time-dependent variable. Post-transplant analyses included Kaplan Meier, Cox PH models, and observed to expected survival ratios. A total of 867 candidates were on ECMO prior to transplant; 247 were identified using new sources of data. Candidates on ECMO had a 23.9 increased adjusted likelihood of waitlist removal for being too sick or death, but only a 4.08 increased adjusted likelihood of transplant. Candidates bridged with ECMO who underwent lung transplant (N=587) experienced an increased overall hazard of post-transplant mortality with veno-arterial and veno-venous configurations conferring HR = 1.67 (95% CI, 1.16, 2.40), HR = 1.45 (95% CI, 1.15, 1.82), respectively. We identified an additional 28.5% of candidates bridged with ECMO prior to transplant using new data. This study of the newly identified full cohort of ECMO candidates demonstrates higher utilization of ECMO as well as an underestimation of waitlist mortality risk factors that should inform strategies to provide timely access to transplant for this population.

Mismatch identified in symptom burden profiles in lung transplantation

BackgroundThere is considerable heterogeneity in symptom burden among lung transplant candidates that may not be explained by objective measures of illness severity. ObjectivesThis study aimed to characterize symptom burden, identify distinct profiles based on symptom burden and illness severity, and determine whether observed profiles are defined by differences in social determinates of health (SDOH). MethodsThis was a prospective study of adult lung transplant candidates. Symptoms were assessed within 3 months of transplant with the Memorial Symptom Assessment Scale (MSAS). MSAS subscale (physical and psychological) scores range 0–4 (higher=more symptom burden). The lung allocation score (LAS) (range 0–100) was our proxy measure of illness severity. The MSAS subscales and LAS were used as continuous indicators in a latent profile analysis to identify distinct symptom-illness severity profiles. Comparative statistics were used to identify SDOH differences among observed profiles. ResultsAmong 93 candidates, 3 distinct symptom-illness severity profiles were identified: 71% had a mild profile in which mild symptoms (MSAS physical 0.49; MSAS psychological 0.57) paired with mild illness severity (LAS 38.59). Of the 29% mismatched participants, 9% had moderate symptoms (MSAS physical 0.88; MSAS psychological 1.47) but severe illness severity (LAS 88.02) and 20% had severe symptoms (MSAS physical 1.30; MSAS psychological 1.94) but mild illness severity (LAS 42.13). The two mismatch profiles were younger, more racially diverse, and had higher psychosocial risk scores. ConclusionSymptom burden is heterogenous, does not always reflect objective measures of illness severity, and may be linked to SDOH.

Relationship of Exercise Capacity, Physical Function, and Frailty Measures With Clinical Outcomes and Healthcare Utilization in Lung Transplantation: A Scoping Review.

Background.Measures of exercise capacity, frailty, and physical function are commonly used in lung transplant candidates and recipients to evaluate their physical limitations and the effects of exercise training and to select candidates for transplantation. It is unclear how these measures are related to clinical outcomes and healthcare utilization before and after lung transplantation. The purpose of this scoping review was to describe how measures of exercise capacity, physical function, and frailty are related to pre- and posttransplant outcomes.Methods.We considered studies of any design that included performance-based tests of exercise capacity, physical function, and frailty in adult lung transplant candidates or recipients. Outcomes of interest were clinical outcomes (eg, mortality, quality of life) and healthcare utilization.Results.Seventy-two articles met the inclusion criteria. The 6-min walk test (6MWT) was shown to be related to mortality on the waiting list with different distance values as cutoffs points. There were inconsistent results regarding the relationship of the 6MWT with other clinical outcomes. Few studies have examined the relationship between the cardiopulmonary exercise test or the short physical performance battery and clinical outcomes, although some studies have shown relationship with survival posttransplant and quality of life. Few studies examined the relationship between the tests of interest and healthcare utilization‚ and the results were inconsistent.Conclusions.Except for the relationship between the 6MWT and mortality on the waiting list, there is limited evidence regarding the relationship of performance-based measures of exercise capacity, frailty, and physical function with clinical outcomes or healthcare utilization.

Symptom-Illness Severity Profiles and Healthcare Use Among Lung Transplant Candidates

<h3>Purpose</h3> Symptoms experienced by lung transplant candidates are heterogenous and may not reflect objective measures of illness severity. Both may contribute to healthcare use. We aimed to identify distinct profiles using integrated data on symptoms and illness severity and examine differences in healthcare use among observed profiles. <h3>Methods</h3> This was a single-center prospective study of adult lung transplant candidates. Symptoms were assessed within 3 months of transplant with the Memorial Symptom Assessment Scale (MSAS). Two subscales, the MSAS physical and psychological, were calculated by averaging the severity, frequency, and distress scores for 12 physical and 6 psychological symptoms (score range 0-4, higher=more severe). The LAS, a score (0-100) that represents illness severity and survival benefit, was our measure of illness severity and obtained from the health record at time of MSAS completion. Latent class analysis was used to identify distinct symptom-illness severity profiles based on two MSAS subscales and LAS. Differences in pretransplant hospitalization rates and posttransplant length of stay (LOS) among profiles were determined by comparative statistics. <h3>Results</h3> Among 93 candidates, three distinct symptom-illness severity profiles were identified: 71% had congruent symptom-illness severity; mild symptoms (MSAS phys 0.49; MSAS psych 0.57) matched mild illness severity (LAS 39.75) and 29% had symptom-illness severity mismatch; 9% had moderate symptoms (MSAS phys 0.88; MSAS psych 1.47) but severe illness severity (LAS 83.59) and 20% had severe symptoms (MSAS phys 1.30; MSAS psych 1.94) but mild illness severity (LAS 42.64). Compared to the congruent profile, mismatch profiles were younger (65 vs 53 and 52 years, p=0.007), more racially diverse (% white: 88 vs 62 and 63, p=0.002), with higher psychosocial risk scores (7.5 vs 10.5 and 13, p=0.03). Hospitalization at time of transplant was more common among the mismatch profiles compared to the congruent profile (11% vs 50% and 26%, p=0.02). Post-transplant hospital LOS did not significantly differ (p= 0.5). <h3>Conclusion</h3> We found incongruence between symptom and illness severity in a subset of patients. Higher rates of pretransplant hospitalization were observed among the mismatch profiles suggesting that both severity of symptoms and illness may be clinically relevant drivers of pretransplant healthcare use.

Pre-transplant vaccination compliance in adult heart and lung transplant recipients.

Vaccine preventable diseases can affect solid organ transplant recipients post-transplant. Therefore, the administration of vaccines and assessment of serologic response should be prioritized in the pre-transplant period. This single-center, retrospective study included 349 adult heart or lung transplant candidates between December 1, 2017 and November 30, 2019. We describe vaccination or serologic status for hepatitis A, hepatitis B, tetanus, pneumococcal, influenza, and other recommended vaccinations among heart or lung transplant candidates. Eighty-two heart transplant candidates (91%) and 77 lung transplant candidates (30%) received an ID consult prior to transplant. More patients completed the pneumococcal series (66.7%vs. 28.6%, P=.045) in the heart transplant group that received an ID consult. In the lung transplant group, patients with an ID consult demonstrated higher rates of immunity to hepatitis A (84.4% vs. 72.9%, P=.047), hepatitis B (75.3% vs. 56.9%, P=.005), and measles (71.4%vs. 52.5%, P=.005) compared to those without. Our results demonstrate the value of consulting ID and administering vaccinations in the early evaluation phase, prior to transplant listing. Opportunities remain to better optimize vaccination rates prior to transplant in heart and lung transplant candidates.

Lung transplant recipient attitudes and beliefs on accepting an organ that is positive for hepatitis C virus.

Little is known about patient perceptions regarding HCV+ organ use in non-HCV-infected recipients. This study examined factors influencing the decision to accept HCV+ organs and the resulting impacts. Adult lung transplant (LT) patients or candidates who had consented to receive an HCV+ organ completed a survey including multiple choice, a five-point Likert scale, and free-text answers. A total of 67 LT recipients or candidates who had consented to receive HCV+ organs were enrolled, of which 21/67 (31%) received HCV+ lungs, 39 (58%) HCV- lungs, and seven (10%) were still waiting. Pre-transplant, 50/67 (75%) patients felt it was either "completely safe" or "very safe" to accept an HCV+ organ. Although 22/67 (33%) said they never or rarely took risks, they still made the decision to accept an HCV+ organ. Common reported reasons were desperation, perception of having "no choice," and increasing symptom severity. In the subset of patients that were transplanted with an HCV+ organ (n=21), only 12.5% reported second thoughts about accepting. Post-transplant, the majority (87.5%) never felt any anxiety about HCV and most (83%) reported no impact from HCV. Perception of treatment tolerability and ease was highly favorable. Use of HCV+ organs demonstrated minimal detrimental perceived impacts on lung transplant patients. Patients generally found the experience to be very positive.

Frailty and aging-associated syndromes in lung transplant candidates and recipients.

Many lung transplant candidates and recipients are older and frailer compared to previous eras. Older patients are at increased risk for pre- and posttransplant mortality, but this risk is not explained by numerical age alone. This manuscript represents the product of the American Society of Transplantation (AST) conference on frailty. Experts in the field reviewed the latest published research on assessment of elderly and frail lung transplant candidates. Physical frailty, often defined as slowness, weakness, low physical activity, shrinking, and exhaustion, and frailty evaluation is an important tool for evaluation of age-associated dysfunction. Another approach is assessment by cumulative deficits, and both types of frailty are common in lung transplant candidates. Frailty is associated with death or delisting before transplant, and may be associated with posttransplant mortality. Sarcopenia, cognitive dysfunction, depression, and nutrition are other important components for patient evaluation. Aging-associated inflammation, telomere dysfunction, and adaptive immune system senescence may also contribute to frailty. Developing tools for frailty assessment and interventions holds promise for improving patient outcomes before and after lung transplantation.

Short Physical Performance Battery Scores at Lung Transplant Assessment: Relationship to Early Transplant Outcomes and Response to Pre-Habilitation

The short physical performance battery (SPPB) has been used as a measure of phenotypic frailty in adult lung transplant candidates. It is associated with an increased risk of delisting and death pre-transplant, and one-year post transplant mortality. As the SPPB may be used to inform transplant eligibility, we examined if SPPB at transplant assessment predicted early post-transplant outcomes, and if the SPPB was responsive to pre-habilitation. This was a retrospective study of all lung transplant candidates who were accepted for transplant at the University Health Network between June 15, 2016 and December 31, 2018. Supervised rehabilitation is provided pre-transplant for the duration of the waiting period and for the first 3 months post-transplant. SPPB scores were categorized as frail (&lt10/12) and non-frail (&gt or equal to 10/12), based on previously established cut-offs. 150 people were accepted for transplant (53% male, 61 IQR [52-67] years, 59% had interstitial lung disease (ILD), six minute walk distance (6MWD) 341 ± 107m) of which 26% were frail. 131 (87%) underwent transplant by December 31, 2018. After adjusting for age, sex and diagnosis, frailty was associated with a lower 6-minute walk distance pre-transplant [mean difference -97 meters (95%CI (133 to -60), p<0.0001] but not with post-transplant hospital length of stay or 3 month post transplant mortality, 6MWD or gait aid use. A subset of 62 people underwent at least 6 weeks of pre-habilitation (37% male, 62 IQR [56-67] years, 60% with ILD, 21% were frail). While the 6-minute walk distance did not change (362 ± 86 vs. 356 ± 101 m, p=0.43), the total SPPB score increased (pre: 11 [10-12) vs. post: 12 [11-12], p=0.01). Improvement occurred in the sit to stand component (pre: 11.42 ± 4.4 vs. post: 9.86 ± 2.8 seconds, p=0.007). A quarter of lung transplant candidates in this cohort exhibited phenotypic frailty at the time of transplant assessment. A SPPB score of &lt 10 at transplant assessment was associated with decreased exercise capacity pre-transplant but not with early post-transplant outcomes. The SPPB score increased after six weeks of pre-habilitation, which may be reflected by an increase in lower extremity strength.

The Palliative Care Needs of Lung Transplant Candidates

Palliative care (PC) has been shown to improve outcomes for seriously ill patients but has not been fully integrated into the care of lung transplant patients. Little is known about the palliative care needs for this population. Our goal was to describe adult lung transplant candidates' perspectives of their PC needs. Prospective, cross-sectional study; Pre-lung transplant patients from a large, single-center adult lung transplant program between February and October 2019, rated their PC needs using an adapted version of the Needs at the End-of-Life Screening Tool (NEST- 13). Each item was scored on a 10-point scale with higher scores indicating greater needs. The sample included 113 lung transplant candidates. Most (66.3%) were undergoing evaluation, 18.4% were waitlisted, and 15.3% had completed evaluation testing but were not yet listed. Almost 74% of the participants undergoing pre-transplant evaluation were outpatient and 26.2% were inpatients. Participants were predominantly middle-aged (mean: 55.5 years, SD:13.6), Caucasian (83.0%) and female (58.0%). The highest-rated PC needs were "difficulty being as physically active as you would like" (mean= 7.9; SD= 2.5), "suffer from physical symptoms" (mean= 7.4; SD= 2.5), "have to miss or cut back on work due to your illness" (mean=6.2; SD= 3.2), "distressed by the thought your life might end" (mean=5.1; SD= 3.6), and "difficulty preparing family and friends for possibility of losing you" (mean= 4.8; SD= 3.8). Psychiatric symptoms were not rated as a significant need. Participants reported that spirituality is important but did not report difficulty meeting this need. Only 7.1% reported seeing a PC specialist and many (48.2%) were unsure what a PC specialist is. Despite concerns regarding end-of-life, 60.7% indicated that they had not discussed their views on death and dying with their health care team. Lung transplant candidates have significant PC needs, particularly related to their physical symptoms, restrictions on their daily activities, and end-of-life concerns. More research is needed to test the effectiveness of PC in meeting the physical and psychosocial needs of lung transplant patients and to examine the most effective approaches for integrating PC into regular, ongoing lung transplant care.

Evaluating Resilience as a Predictor of Outcomes in Lung Transplant Candidates

Resilience can be defined as a patient's capacity to adapt to or recover from adverse experiences. We hypothesize that resilience may be an important factor associated with lung transplant outcomes. Our objective was to describe resilience in lung transplant candidates and examine resilience as a potential predictor of lung transplant outcomes. Adult lung transplant candidates on the waiting list between 9/16/2015 to 10/1/2019 at six transplant centers were mailed prospective questionnaires which included the validated Connor-Davidson Resilience Scale (RISC-10). Non-responders were declared non-participators after three recruitment attempts by mail. Demographics and transplant-related outcomes were recorded. Survey metrics were excellent with 56.9% participation (N = 199) and <0.05% missing item responses. Participants had a mean age of 59 (± 9) years. A majority of participants were female (51%), white (93%), and married (71%). Mean pre-transplant RISC-10 score was 32.0 ± 5.6, similar to population norms (32.1 ± 5.8). However, 31 participants (16%) had a RISC-10 score ≥1 SD below population norms (≤ 26.3). Low RISC-10 score participants did not differ from the others by race, sex, age, or primary diagnosis. The average duration of follow-up was 7.7 months. During the study, 110 participants were transplanted, 18 delisted, 22 died while listed, and 49 remained waiting. Post-transplant deaths were limited (N = 18). Of survivors, 88 completed post-transplant surveys (80%). Post-transplant scores increased by 1.4 (95% CI 0.29 to 2.6; p = 0.01) however this is less than the minimum clinically important difference (≥2.9). RISC-10 was not associated with death, delisting or health-related quality of life measures. In single-item analysis, stress-related questions scored lower than other questions. In lung transplant candidates, resilience was comparable to population norms. However, one in six lung transplant candidates had low resilience. Addressing stress may be a potential target for improving resilience in future studies.

Impact of Affect on Lung Transplant Candidate Outcomes.

We examined the association of adult lung transplant candidates' self-reported affect with transplant-related outcomes, evaluating whether a positive (vs negative) frame of mind might be protective. Consenting waitlisted candidates from 6 centers completed the questionnaires including the Positive and Negative Affect Schedule annually and posttransplant. Univariate logistic regression analysis was performed to determine the association of baseline affect with outcomes of death or delisting. Models were subsequently adjusted for age, marital status, and education. Questionnaires were completed by 169 candidates (77.9% participation). Mean positive affect, negative affect, and positive-to-negative affect ratio (positivity ratio) were similar to expected norms. The scores of the questionnaire did not change significantly over time. Fifteen (8.9%) waitlisted participants died. Candidates who died while waiting had lower positivity ratios compared to those who survived (1.82 vs 2.45; P = .02). A more negative affect was associated with increased death on the waiting list (adjusted odds ratio [OR] 1.10; P = .021). Conversely, a higher positivity ratio was associated with decreased death while waiting (adjusted OR: 0.45; P = .027). Negative affect may represent a novel risk factor for death on the waitlist. Enhancing positive affect may represent a useful target for psychological optimization in lung transplant candidates.

A nonlinear relationship between visceral adipose tissue and frailty in adult lung transplant candidates.

Frailty is a state of decreased physiologic reserve associated with poor outcomes before and after lung transplantation. Obesity, particularly central obesity characterized by excess proinflammatory visceral adipose tissue (VAT), is associated with incident frailty in middle-aged and older adults. The association between VAT and frailty in advanced lung disease, however, is unknown. In two, nonoverlapping multicenter cohorts of adults listed for lung transplantation, we measured VAT area on bioelectrical impedance assay (BIA) in one cohort and cross-sectional VAT and subcutaneous adipose tissue (SAT) areas on abdominal computed tomography (CT) in the other. We identified a nonlinear relationship between greater VAT by BIA and frailty. In fully adjusted piecewise regression models, every 20cm2 increase in VAT area was associated with 50% increased odds of frailty in subjects with high VAT (95% CI 1.2-1.9, P<.001), and 10% decreased odds of frailty (95% CI 0.7-1.04, P=.12) in subjects with low VAT. Compared to frail subjects with low VAT, those with high VAT were more likely to have low grip strength and less likely to have weight loss, suggesting that mechanisms of frailty may differ by VAT. Further investigation of mechanisms linking VAT and frailty may identify new targets for prevention and treatment.

Association between Allosensitization and Waiting List Outcomes among Adult Lung Transplant Candidates in the United States.

Rationale: Allosensitization may be a barrier to lung transplant. Currently, consideration is not given to allosensitization when assigning priority on the lung transplant waiting list. Objectives: We aimed to examine the association between allosensitization and waiting list outcomes. Methods: We conducted a retrospective single-center cohort study of adults listed for lung transplant at our center between January 1, 2006, and December 31, 2016. We screened candidates for human leukocyte antigen antibodies before listing and examined the association between allosensitization and waiting list outcomes, including likelihood of transplant and death on the waiting list, using a competing risk model. Calculated panel-reactive antibody (CPRA) was used as a continuous measure of allosensitization. Results: Among 746 candidates who were listed for lung transplant during the study period, 263 (35%) were allosensitized, and 483 (65%) were not. In unadjusted analysis, allosensitized candidates had a decreased likelihood of transplant compared with nonallosensitized candidates (subhazard ratio [sHR], 0.71; 95% confidence interval [CI], 0.60-0.83; P < 0.001) and were more likely to die on the waiting list (sHR, 1.66; 95% CI, 1.08-2.58; P < 0.001). In multivariable modeling, increasing CPRA was associated with an increased risk of death and a decreased likelihood of transplant (sHR for death, 1.15 per 10% increase in CPRA; 95% CI, 1.07-1.22; P < 0.001; sHR for transplant, 0.89 per 10% increase in CPRA; 95% CI, 0.86-0.91; P < 0.001). Conclusions: Broad allosensitization was associated with longer waiting times, decreased likelihood of transplant, and increased risk of death among candidates on the waiting list for lung transplant. Consideration of allosensitization in organ allocation strategies might help mitigate this increased risk in highly allosensitized candidates.

Differences Between Patients With Idiopathic Pleuroparenchymal Fibroelastosis and Those With Other Types of Idiopathic Interstitial Pneumonia in Candidates for Lung Transplants

IntroductionThe prognostic implications of having patients with idiopathic pleuroparenchymal fibroelastosis (IPPFE) on lung transplantation waiting lists have been unclear. In Japan, where a severe shortage of brain-dead donors remains a major limitation for organ transplantation, it is particularly important to predict the prognoses of patients when they are listed for transplantation. The purpose of this study was to investigate the characteristics of lung transplantation candidates with IPPFE and the influence of those characteristics on prognosis. MethodsThis was a retrospective review of 29 consecutive adult lung transplant candidates with idiopathic interstitial pneumonia between January 2014 and April 2018. ResultsEight patients with IPPFE and 21 with other types of idiopathic interstitial pneumonia were included. Body mass index (median 17.1 kg/m2 vs 23.5 kg/m2, P < .01) and ratio of anteroposterior to transverse diameter of the thoracic cage were significantly lower (0.530 vs 0.583, P = .02) in the IPPFE group. Patients with a body mass index <20.0 kg/m2 (P = .02), 6-minute walk distance <250.0 m (P < .01), ratio of PaO2 to fraction of inspiratory oxygen <300.0 mm Hg (P < .01), and an inability to perform the diffusing capacity of carbon monoxide test (P < .01) had significantly shorter survival times in the other idiopathic interstitial pneumonia, but not in the IPPFE, group. Some patients with IPPFE survived for long enough to undergo transplantation. ConclusionsPatients with IPPFE waiting for transplantation have some distinctive characteristics and should be retained on waiting lists to receive transplants.

A mobile health technology enabled home-based intervention to treat frailty in adult lung transplant candidates: A pilot study.

Frailty is prevalent in lung transplant candidates (LTC) and is associated with waitlist delisting or death. We performed a pilot study to assess the safety and feasibility of a home-based, mobile health technology-facilitated intervention to treat frailty in LTC. We performed an 8-week, nonrandomized, home-based exercise and nutrition intervention in LTC with Short Physical Performance Battery (SPPB) frailty scores of ≤11. The intervention utilized a customized, mobile device application ("app") enabling monitoring and progression of the intervention in real time. We aimed to evaluate key process measures. Secondarily, we tested whether the intervention could improve frailty scores quantified by the SPPB and Fried Frailty Phenotype (FFP). A total of 15 subjects enrolled were 63±5.7years old; oxygen requirements ranged from 3 to 15LPM. Thirteen subjects completed the intervention. Over 108 subject-weeks, there were no adverse events. Subjects found the app engaging and easy to work with. SPPB frailty improved in 7 (54%) and FFP improved in 8 (62%). There was a strong trend toward improved frailty scores (SPPB change 1.0±1.9; P=.08; FFP change -0.6±1.0; P=.07). In this pilot study, we found that a home-based prehabilitation program that leverages mobile health technology to target frailty in LTC is well received, safe, and capable of improving physical frailty scores.

Frailty and maximal exercise capacity in adult lung transplant candidates.

Frail lung transplant candidates are more likely to be delisted or die without receiving a transplant. Further knowledge of what frailty represents in this population will assist in developing interventions to prevent frailty from developing. We set out to determine whether frail lung transplant candidates have reduced exercise capacity independent of disease severity and diagnosis. Sixty-eight adult lung transplant candidates underwent cardiopulmonary exercise testing (CPET) and a frailty assessment (Fried's Frailty Phenotype (FFP)). Primary outcomes were peak workload and peak aerobic capacity (V˙O2). We used linear regression to adjust for age, gender, diagnosis, and lung allocation score (LAS). The mean±SD age was 57±11 years, 51% were women, 57% had interstitial lung disease, 32% had chronic obstructive pulmonary disease, 11% had cystic fibrosis, and the mean LAS was 40.2 (range 19.2-94.5). In adjusted models, peak workload decreased by 10W (95% CI 4.7 to 14.6) and peak V˙O2 decreased by 1.8mL/kg/min (95% CI 0.6 to 2.9) per 1 unit increment in FFP score. After adjustment, exercise tolerance was 38W lower (95% CI 18.4 to 58.1) and peak V˙O2 was 8.5mL/kg/min lower (95% CI 3.3 to 13.7) among frail participants compared to non-frail participants. Frailty accounted for 16% of the variance (R2) of watts and 19% of the variance of V˙O2 in adjusted models. Frailty contributes to reduced exercise capacity among lung transplant candidates independent of disease severity.

Chest Fat Quantification via CT Based on Standardized Anatomy Space in Adult Lung Transplant Candidates.

PurposeOverweight and underweight conditions are considered relative contraindications to lung transplantation due to their association with excess mortality. Yet, recent work suggests that body mass index (BMI) does not accurately reflect adipose tissue mass in adults with advanced lung diseases. Alternative and more accurate measures of adiposity are needed. Chest fat estimation by routine computed tomography (CT) imaging may therefore be important for identifying high-risk lung transplant candidates. In this paper, an approach to chest fat quantification and quality assessment based on a recently formulated concept of standardized anatomic space (SAS) is presented. The goal of the paper is to seek answers to several key questions related to chest fat quantity and quality assessment based on a single slice CT (whether in the chest, abdomen, or thigh) versus a volumetric CT, which have not been addressed in the literature.MethodsUnenhanced chest CT image data sets from 40 adult lung transplant candidates (age 58 ± 12 yrs and BMI 26.4 ± 4.3 kg/m2), 16 with chronic obstructive pulmonary disease (COPD), 16 with idiopathic pulmonary fibrosis (IPF), and the remainder with other conditions were analyzed together with a single slice acquired for each patient at the L5 vertebral level and mid-thigh level. The thoracic body region and the interface between subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) in the chest were consistently defined in all patients and delineated using Live Wire tools. The SAT and VAT components of chest were then segmented guided by this interface. The SAS approach was used to identify the corresponding anatomic slices in each chest CT study, and SAT and VAT areas in each slice as well as their whole volumes were quantified. Similarly, the SAT and VAT components were segmented in the abdomen and thigh slices. Key parameters of the attenuation (Hounsfield unit (HU) distributions) were determined from each chest slice and from the whole chest volume separately for SAT and VAT components. The same parameters were also computed from the single abdominal and thigh slices. The ability of the slice at each anatomic location in the chest (and abdomen and thigh) to act as a marker of the measures derived from the whole chest volume was assessed via Pearson correlation coefficient (PCC) analysis.ResultsThe SAS approach correctly identified slice locations in different subjects in terms of vertebral levels. PCC between chest fat volume and chest slice fat area was maximal at the T8 level for SAT (0.97) and at the T7 level for VAT (0.86), and was modest between chest fat volume and abdominal slice fat area for SAT and VAT (0.73 and 0.75, respectively). However, correlation was weak for chest fat volume and thigh slice fat area for SAT and VAT (0.52 and 0.37, respectively), and for chest fat volume for SAT and VAT and BMI (0.65 and 0.28, respectively). These same single slice locations with maximal PCC were found for SAT and VAT within both COPD and IPF groups. Most of the attenuation properties derived from the whole chest volume and single best chest slice for VAT (but not for SAT) were significantly different between COPD and IPF groups.ConclusionsThis study demonstrates a new way of optimally selecting slices whose measurements may be used as markers of similar measurements made on the whole chest volume. The results suggest that one or two slices imaged at T7 and T8 vertebral levels may be enough to estimate reliably the total SAT and VAT components of chest fat and the quality of chest fat as determined by attenuation distributions in the entire chest volume.