Depressive symptoms in lung transplant recipients: trajectory and association with mortality and allograft dysfunction.

OBJECTIVE: Most studies observing an association between depressive symptoms following lung transplantation and mortality are limited to depressive symptom measurement at a single time point, unrelated to allograft function. We aimed to test the association of depressive symptoms over multiple assessments with allograft dysfunction and with mortality. METHODS: We assessed depressive symptoms before and serially up to 3 years after lung transplantation in lung transplant recipients. We quantified depressive symptoms with the Geriatric Depression Scale (GDS; range 0-15; minimally important difference (MID): 2). We quantified changes in GDS using linear mixed effects models and tested the association with mortality using Cox proportional hazards models with GDS as a time-dependent predictor. To determine if worsening in GDS preceded declines in lung function, we tested the association of GDS as a time-dependent predictor with the lagged outcome of FEV1 at the following study visit. RESULTS: Among 266 participants, depressive symptoms improved early after transplantation. Worsening in post-transplant GDS by the MID was associated with mortality (HR 1.25, 95% CI 1.05 to 1.50), and in lagged outcome analyses with decreased per cent predicted FEV1 (Δ, -1.62%, 95% CI -2.49 to -0.76). Visual analyses of temporal changes in GDS demonstrated that worsening depressive symptoms could precede chronic lung allograft dysfunction. CONCLUSIONS: Depressive symptoms generally improve after lung transplantation. When they worsen, however, there is an association with declines in lung function and mortality. Depression is one of the few, potentially modifiable, risk factors for chronic lung allograft dysfunction and death.

Primary graft dysfunction attenuates improvements in health-related quality of life after lung transplantation, but not disability or depression.

Disability, depressive symptoms, and impaired health-related quality of life (HRQL) are common among patients with life-threatening respiratory compromise. We sought to determine if primary graft dysfunction (PGD), a syndrome of acute lung injury, attenuates improvements in patient-reported outcomes after transplantation. In a single-center prospective cohort, we assessed disability, depressive symptoms, and HRQL before and at 3- to 6-month intervals after lung transplantation. We estimated the magnitude of change in disability, depressive symptoms, and HRQL with hierarchical segmented linear mixed-effects models. Among 251 lung transplant recipients, 50 developed PGD Grade 3. Regardless of PGD severity, participants had improvements in disability and depressive symptoms, as well as generic-physical, generic-mental, respiratory-specific, and health-utility HRQL, exceeding 1- to 4-fold the minimally clinically important difference across all instruments. Participants with PGD Grade 3 had a lower magnitude of improvement in generic-physical HRQL and health-utility than in all other participants. Among participants with PGD Grade 3, prolonged mechanical ventilation was associated with greater attenuation of improvements. PGD remains a threat to the 2 primary aims of lung transplantation, extending survival and improving HRQL. Attenuation of improvement persists long after hospital discharge. Future studies should assess if interventions can mitigate the impact of PGD on patient-reported outcomes.

The association of post-operative delirium with patient-reported outcomes and mortality after lung transplantation.

Post-operative delirium after lung transplantation is common. Its associations with health-related quality of life (HRQL), depression, and mortality remains unknown. In 236 lung transplant recipients, HRQL and depressive symptoms were assessed as part of a structured survey battery before and after transplantation. Surveys included the Geriatric Depressive Scale (GDS) and Short Form 12 (SF12). Delirium was assessed throughout the post-operative intensive care unit (ICU) stay with Confusion Assessment Method for ICU. Delirium and mortality data were extracted from electronic medical records. We examined associations between delirium and changes in depressive symptoms and HRQL using linear mixed effects models and association between delirium and mortality with Cox-proportional hazard models. Post-operative delirium occurred in 34 participants (14%). Delirium was associated with attenuated improvements in SF12-PCS (difference ₋4.0; 95%CI: -7.4, -0.7) but not SF12-MCS (difference 2.2; 95%CI: -0.7,5.7) or GDS (difference ₋0.4; 95%CI: -1.5,0.7). Thirty-two participants died during the study period. Delirium was associated with increased adjusted hazard risk of mortality (HR 17.9, 95%CI: 4.4,72.5). Delirium after lung transplantation identifies a group at increased risk for poorer HRQL and death within the first post-operative year. Further studies should investigate potential causal links between delirium, and poorer HRQL and mortality risk after lung transplantation.

Mitochondrial DNA Stimulates TLR9-Dependent Neutrophil Extracellular Trap Formation in Primary Graft Dysfunction.

The immune system is designed to robustly respond to pathogenic stimuli but to be tolerant to endogenous ligands to not trigger autoimmunity. Here, we studied an endogenous damage-associated molecular pattern, mitochondrial DNA (mtDNA), during primary graft dysfunction (PGD) after lung transplantation. We hypothesized that cell-free mtDNA released during lung ischemia-reperfusion triggers neutrophil extracellular trap (NET) formation via TLR9 signaling. We found that mtDNA increases in the BAL fluid of experimental PGD (prolonged cold ischemia followed by orthotopic lung transplantation) and not in control transplants with minimal warm ischemia. The adoptive transfer of mtDNA into the minimal warm ischemia graft immediately before lung anastomosis induces NET formation and lung injury. TLR9 deficiency in neutrophils prevents mtDNA-induced NETs, and TLR9 deficiency in either the lung donor or recipient decreases NET formation and lung injury in the PGD model. Compared with human lung transplant recipients without PGD, severe PGD was associated with high levels of BAL mtDNA and NETs, with evidence of relative deficiency in DNaseI. We conclude that mtDNA released during lung ischemia-reperfusion triggers TLR9-dependent NET formation and drives lung injury. In PGD, DNaseI therapy has a potential dual benefit of neutralizing a major NET trigger (mtDNA) in addition to dismantling pathogenic NETs.

Frailty after lung transplantation is associated with impaired health-related quality of life and mortality.

BACKGROUND: Lung transplantation and related medications are associated with pathobiological changes that can induce frailty, a state of decreased physiological reserve. Causes of persistent or emergent frailty after lung transplantation, and whether such transplant-related frailty is associated with key outcomes, are unknown. METHODS: Frailty and health-related quality of life (HRQL) were prospectively measured repeatedly for up to 3 years after lung transplantation. Frailty, quantified by the Short Physical Performance Battery (SPPB), was tested as a time-dependent binary and continuous predictor. The association of transplant-related frailty with HRQL and mortality was evaluated using mixed effects and Cox regression models, respectively, adjusting for age, sex, ethnicity, diagnosis, and for body mass index and lung function as time-dependent covariates. We tested the association between measures of body composition, malnutrition, renal dysfunction and immunosuppressants on the development of frailty using mixed effects models with time-dependent predictors and lagged frailty outcomes. RESULTS: Among 259 adults (56% male; mean age 55.9±12.3 years), transplant-related frailty was associated with lower HRQL. Frailty was also associated with a 2.5-fold higher mortality risk (HR 2.51; 95% CI 1.21 to 5.23). Further, each 1-point worsening in SPPB was associated, on average, with a 13% higher mortality risk (HR 1.13; 95% CI 1.04 to 1.23). Secondarily, we found that sarcopenia, underweight and obesity, malnutrition, and renal dysfunction were associated with the development of frailty after transplant. CONCLUSIONS: Transplant-related frailty is associated with lower HRQL and higher mortality in lung recipients. Abnormal body composition, malnutrition and renal dysfunction may contribute to the development of frailty after transplant. Confirming the role of these potential contributors and developing interventions to mitigate frailty may improve lung transplant success.

Development and Preliminary Validation of the Lung Transplant Quality of Life (LT-QOL) Survey.

RATIONALE: Although lung transplantation aims to improve health-related quality of life (HRQL), existing instruments fail to include health domains considered important in this population. OBJECTIVES: We aimed to develop a comprehensive lung transplant-specific instrument to address this shortcoming. METHODS: We developed a pool of 126 candidate items addressing domains previously identified as important by lung transplant recipients. Through cognitive interviews conducted in 43 transplant recipients, items deemed irrelevant or redundant were dropped. The 84 remaining items were field tested in lung transplant recipients. Exploratory and confirmatory factor analyses were used to evaluate the factor structure, and scales were evaluated for internal consistency and construct validity. MEASUREMENTS AND MAIN RESULTS: The 84-item preliminary survey was administered to 201 lung transplant recipients with a mean age of 57.9 (±12.7) years; 46% were female. After factor analyses and internal consistency evaluation, we retained 60 items comprising the Lung Transplant Quality of Life (LT-QOL) Survey. The LT-QOL contains 10 scales that measure symptoms, health perceptions, functioning, and well-being. The confirmatory factor analysis model had good approximate fit (comparative fit index = 0.990; standardized root-mean-square residual = 0.062). Cronbach αs for the 10 scales ranged from 0.75 to 0.95. Interscale correlations were consistent with hypothesized relationships. Subjects with severe chronic lung allograft dysfunction (n = 13) reported significantly worse HRQL than subjects without chronic lung allograft dysfunction (n = 168) on 6 of the 10 LT-QOL scales. CONCLUSIONS: The LT-QOL is a new, multidimensional instrument that characterizes and quantifies HRQL in lung transplant recipients.

Frailty phenotypes and mortality after lung transplantation: A prospective cohort study.

Frailty is associated with increased mortality among lung transplant candidates. We sought to determine the association between frailty, as measured by the Short Physical Performance Battery (SPPB), and mortality after lung transplantation. In a multicenter prospective cohort study of adults who underwent lung transplantation, preoperative frailty was assessed with the SPPB (n = 318) and, in a secondary analysis, the Fried Frailty Phenotype (FFP; n = 299). We tested the association between preoperative frailty and mortality following lung transplantation with propensity score-adjusted Cox models. We calculated postestimation marginalized standardized risks for 1-year mortality by frailty status using multivariate logistic regression. SPPB frailty was associated with an increased risk of both 1- and 4-year mortality (adjusted hazard ratio [aHR]: 7.5; 95% confidence interval [CI]: 1.6-36.0 and aHR 3.8; 95%CI: 1.8-8.0, respectively). Each 1-point worsening in SPPB was associated with a 20% increased risk of death (aHR: 1.20; 95%CI: 1.08-1.33). Frail subjects had an absolute increased risk of death within the first year after transplantation of 12.2% (95%CI: 3.1%-21%). In secondary analyses, FFP frailty was associated with increased risk of death within the first postoperative year (aHR: 3.8; 95%CI: 1.1-13.2) but not over longer follow-up. Preoperative frailty is associated with an increased risk of death after lung transplantation.

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

BACKGROUND: 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. METHODS: 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). RESULTS: A total of 15 subjects enrolled were 63 ± 5.7 years 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). CONCLUSION: 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.

Improvements in frailty contribute to substantial improvements in quality of life after lung transplantation in patients with cystic fibrosis.

BACKGROUND: While lung transplantation (LTx) improves health-related quality of life (HRQL) in cystic fibrosis (CF), the determinants of this improvement are unknown. In other populations, frailty-a syndrome of vulnerability to physiologic stressors-is associated with disability and poor HRQL. We hypothesized that improvements in frailty would be associated with improved disability and HRQL in adults with CF undergoing LTx. METHODS: In a single-center prospective cohort study from 2010 to 2017, assessments of frailty, disability, and HRQL were performed before and at 3- and 6-months after LTx. We assessed frailty by the short physical performance battery (SPPB). We assessed disability with the Lung Transplant Valued Life Activities scale (LT-VLA) and HRQL by the Medical Outcomes Study Short Form Physical and Mental Component Summary scales (SF12-PCS, -MCS), the Airway Questionnaire 20-Revised (AQ20R), and the Euroqol 5D (EQ5D). We tested the association of concurrent changes in frailty and lung function on disability and HRQL by linear mixed-effects models adjusted for sex and body mass index. RESULTS: Among 23 participants with CF, improvements in frailty and lung function were independently associated with improved disability and some HRQL measures. For example, each 1-point improvement in SPPB or 200 mL improvement in FEV1 was associated with improved LT-VLA disability by 0.14 (95%CI: 0.08-0.20) and 0.07 (95%CI: 0.05-0.09) points and improved EQ5D by 0.05 (95%CI: 0.03 to 0.07) and 0.02 (95%CI: 0.01-0.03) points, respectively. CONCLUSION: Improvement in frailty is a novel determinant of improved disability and HRQL in adults with CF undergoing LTx.

Frailty trajectories in adult lung transplantation: A cohort study.

BACKGROUND: Frailty is common in adults with advanced lung disease and is associated with death before and after lung transplantation. We aimed to determine whether frailty changes from before to after the lung transplant. METHODS: In a single-center, prospective cohort study among adults undergoing lung transplantation from 2010 to 2017, we assessed frailty by the Short Physical Performance Battery (SPPB; higher scores reflect less frailty) and Fried Frailty Phenotype (FFP; higher scores reflect greater frailty) before and repeatedly up to 36 months after transplant. We tested for changes in frailty scores over time using segmented mixed effects models, adjusting for age, sex, and diagnosis. We quantified the proportion of subjects transitioning between frailty states (frail vs not frail) from before to after the transplant. RESULTS: In 246 subjects, changes in frailty occurred within the first 6 post-operative months and remained stable thereafter. The overall change in frailty was attributable to improvements among those subjects who were frail before transplant. They experienced a 5.1-point improvement in SPPB (95% confidence interval [CI] 4.6-5.7) and a 1.8-point improvement in FFP (95% CI -2.1 to -1.6) during the early period. Frailty by SPPB and FFP did not change in those who were not frail before transplant. Approximately 84% of survivors who were frail before transplant became not frail after transplant. CONCLUSIONS: Pre-operative frailty resolves in many patients after lung transplantation. Because a large proportion of frailty may be attributable to advanced lung disease, frailty alone should not be an absolute contraindication to transplantation.

Moving Pulmonary Rehabilitation Into the Home: A CLINICAL REVIEW.

Pulmonary rehabilitation (PR) is the standard of care for persons with chronic, symptomatic lung disease. The availability of PR is limited, particularly in rural areas. In addition, barriers to PR include the lack of transportation, patient inconvenience, inadequate insurance coverage, and cost. Technology has the potential to overcome several barriers to PR by enhancing the availability and uptake of PR principles through the development of technology-supported, home-based PR programs. For technology-supported, home-based PR, or telehealth PR, to be effective, key components of traditional PR must be present including appropriate individualized exercise prescription, self-management education, outcome measurements, and patient support. This clinical review summarizes the current practice of PR, describes limitations to the availability of PR, describes key principles that technology should feature to ensure best practices are met, and proposes current and future technology options as an emerging strategy for home delivery of PR and its components.

Improvement in patient-reported outcomes after lung transplantation is not impacted by the use of extracorporeal membrane oxygenation as a bridge to transplantation.

OBJECTIVE: Extracorporeal membrane oxygenation (ECMO) is increasingly used as a bridge to lung transplantation. The impact of preoperative ECMO on health-related quality of life (HRQL) and depressive symptoms after lung transplantation remains unknown, however. METHODS: In a single-center prospective cohort study, we assessed HRQL and depressive symptoms before and at 3, 6, and 12 months after lung transplantation using the Short Form 12 Physical and Mental Component Scores (SF12-PCS and SF12-MCS), Airway Questionnaire 20-Revised (AQ20R), EuroQol 5D (EQ5D), and Geriatric Depression Scale (GDS). Changes in HRQL were quantified by segmented linear mixed-effects models controlling for age, sex, diagnosis, preoperative forced expiratory volume in 1 second, 6-minute walk distance, and Lung Allocation Score. We compared changes in HRQL among subjects bridged with ECMO, subjects hospitalized but not on ECMO, and subjects called in for transplantation as outpatients. RESULTS: Out of 189 subjects, 17 were bridged to transplantation with ECMO. In all groups, improvements in HRQL following lung transplantation exceeded the minimally clinically important difference using the SF12-PCS, AQ20R, EQ5D, and GDS. HRQL defined by SF12-MCS did not change after transplantation. Improvements were generally similar among the groups, except for EQ5D, which showed a trend toward less benefit in the outpatients, possibly due to their better HRQL before lung transplantation. CONCLUSIONS: Subjects ill enough to require ECMO as a bridge to lung transplantation appear to achieve similar improvements in HRQL and depressive symptoms as those who do not. It is reassuring to both providers and patients that lung transplantation provides substantial improvements in HRQL, even for those patients who are critically ill in the run up to transplantation.