One-year change in the health status predicts the subsequent hospitalization and mortality in patients waitlisted for lung transplantation in Japan

BACKGROUND

Poor health-related quality of life (HRQL) at the registration for lung transplantation is related to waitlist mortality. We investigated the relationship between 1-year change in HRQL and subsequent outcomes in patients waitlisted for lung transplantation.

METHODS

In a 5-year longitudinal study, we analyzed the factors related to waitlist mortality in 197 lung transplant patients registered on the Japan Organ Transplant Network. HRQL was assessed using St. George's Respiratory Questionnaire (SGRQ), and factors related to changes in SGRQ scores were evaluated after 1 year. We assessed the relationship between the 1-year change in SGRQ score and subsequent mortality or hospitalization.

RESULTS

Among 197 patients, 108 remained waitlisted during the first-year assessment. During the median follow-up period of 469 d, 28 patients died, and 54 underwent lung transplantation. Univariate Cox proportional hazards analysis revealed that the changes in all components and total score of the SGRQ after 1 year were associated with waitlist mortality (p < 0.05). Stepwise multivariate analysis revealed that the 1-year changes in SGRQ scores were significantly related to waitlist mortality. Forty-three patients with worsened HRQL after 1 year had higher likelihoods of hospitalization (p = 0.038) and mortality (p = 0.026) after 1 and 4 years of follow-up, respectively, than 61 patients without worsened HRQL.

CONCLUSIONS

Patients with worsened health status during the first year after registration had higher likelihoods of hospitalization and mortality after 1 and 4 years of follow-up, respectively, than those without worsened HRQL. Strategies to improve health status while waiting are needed to reduce waitlist hospitalization or mortality.

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

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.

The Lung Allocation Score and Its Relevance

Lung transplantation in the United States, under oversight by the Organ Procurement Transplantation Network (OPTN) in the 1990s, operated under a system of allocation based on location within geographic donor service areas, wait time of potential recipients, and ABO compatibility. On May 4, 2005, the lung allocation score (LAS) was implemented by the OPTN Thoracic Organ Transplantation Committee to prioritize patients on the wait list based on a balance of wait list mortality and posttransplant survival, thus eliminating time on the wait list as a factor of prioritization. Patients were categorized into four main disease categories labeled group A (obstructive lung disease), B (pulmonary hypertension), C (cystic fibrosis), and D (restrictive lung disease/interstitial lung disease) with variables within each group impacting the calculation of the LAS. Implementation of the LAS led to a decrease in the number of wait list deaths without an increase in 1-year posttransplant survival. LAS adjustments through the addition, modification or elimination of covariates to improve the estimates of patient severity of illness, have since been made in addition to establishing criteria for LAS value exceptions for pulmonary hypertension patients. Despite the success of the LAS, concerns about the prioritization, and transplantation of older, sicker individuals have made some aspects of the LAS controversial. Future changes in US lung allocation are anticipated with the current development of a continuous distribution model that incorporates the LAS, geographic distribution, and unaccounted aspects of organ allocation into an integrated score.

Patient-reported dyspnea and health predict waitlist mortality in patients waiting for lung transplantation in Japan

BACKGROUND

Waitlist mortality due to donor shortage for lung transplantation is a serious problem worldwide. Currently, the selection of recipients in Japan is mainly based on the registration order. Hence, scientific evidence for risk stratification regarding waitlist mortality is urgently needed. We hypothesized that patient-reported dyspnea and health would predict mortality in patients waitlisted for lung transplantation.

METHODS

We analyzed factors related to waitlist mortality using data of 203 patients who were registered as candidates for lung transplantation from deceased donors. Dyspnea was evaluated using the modified Medical Research Council (mMRC) dyspnea scale, and the health status was determined with St. George's Respiratory Questionnaire (SGRQ).

RESULTS

Among 197 patients who met the inclusion criteria, the main underlying disease was interstitial lung disease (99 patients). During the median follow-up period of 572 days, 72 patients died and 96 received lung transplantation (69 from deceased donors). Univariable competing risk analyses revealed that both mMRC dyspnea and SGRQ Total score were significantly associated with waitlist mortality (p = 0.003 and p < 0.001, respectively) as well as age, interstitial lung disease, arterial partial pressure of carbon dioxide, and forced vital capacity. Multivariable competing risk analyses revealed that the mMRC and SGRQ score were associated with waitlist mortality in addition to age and interstitial lung disease.

CONCLUSIONS

Both mMRC dyspnea and SGRQ score were significantly associated with waitlist mortality, in addition to other clinical variables such as patients' background, underlying disease, and pulmonary function. Patient-reported dyspnea and health may be measured through multi-dimensional analysis (including subjective perceptions) and for risk stratification regarding waitlist mortality.

Sleep quality and its association with health-related quality of life of patients on lung transplantation waitlist in Japan

PURPOSE

Poor quality of sleep is a common feature in patients with various lung diseases and affects their health-related quality of life (HRQL). We evaluated sleep quality and HRQL in patients on the waitlist for lung transplantation in Japan.

METHODS

In this prospective study, patient-reported and physiological data were collected from patients newly registered on the waitlist for lung transplantation in Japan. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI) and HRQL using the St. George's Respiratory Questionnaire (SGRQ). The frequency of poor sleep quality, correlations between sleep quality and various clinical parameters, and predictive factors of sleep quality were examined.

RESULTS

Of 193 patients, the three most-frequent indications for lung transplantation were interstitial pneumonia (n = 96), pulmonary complications of hematopoietic stem cell transplantation (n = 25), and pulmonary hypertension (n = 17). Poor sleep quality (PSQI > 5) was observed in 102 patients (53%) and was significantly associated with worse Hospital Anxiety and Depression Score (HADS), worse SGRQ score, worse modified Medical Research Council Dyspnea score, and shorter 6-min walk distance. However, it was not associated with sex, pulmonary function, interstitial pneumonia, or arterial blood gas. Stepwise multiple regression analysis indicated that poor sleep quality was explained significantly by HADS anxiety (23%) and SGRQ Symptoms (10%).

CONCLUSION

Poor sleep quality was found to be common among patients on the lung transplantation waitlist in Japan. The two most significant factors responsible for impaired sleep quality were anxiety and respiratory symptoms. Additional care should be taken to ensuring a better quality of sleep for such patients.

Analysis of Optimal Health-Related Quality of Life Measures in Patients Waitlisted for Lung Transplantation

Background

Improving health-related quality of life (HRQL) is an important goal of lung transplantation, and St. George's Respiratory Questionnaire (SGRQ) is frequently used for assessing HRQL in patients waitlisted for lung transplantation. We hypothesized that chronic respiratory failure (CRF)-specific HRQL measures would be more suitable than the SGRQ, considering the underlying disease and its severity in these patients.

Methods

We prospectively collected physiological and patient-reported data (HRQL, dyspnea, and psychological status) of 199 patients newly registered in the waiting list of lung transplantation. CRF-specific HRQL measures of the Maugeri Respiratory Failure Questionnaire (MRF) and Severe Respiratory Insufficiency Questionnaire (SRI) were assessed in addition to the SGRQ.

Results

Compared to the MRF-26 and SRI, the score distribution of the SGRQ was skewed toward the worse ends of the scale. All domains of the MRF-26 and SRI were significantly correlated with the SGRQ. Multiple regression analyses to investigate factors predicting each HRQL score indicated that dyspnea and psychological status accounted for 12% to 28% of the variance more significantly than physiological measures did. The MRF-26 Total and SRI Summary significantly worsened from the baseline to 1 year (p < 0.001 and p < 0.001 and p < 0.001 and.

Conclusions

The MRF-26 and SRI are valid, discriminative, and responsive in patients waitlisted for lung transplantation. In terms of the score distribution and responsiveness, CRF-specific measures may function better in their HRQL assessment than the currently used measures do.

Evaluation of Skeletal Muscle Function in Lung Transplant Candidates

BACKGROUND

Lung transplantation (LTx) is offered to older and more complex patients who may be at higher risk of skeletal muscle dysfunction, but the clinical implications of this remain uncertain. The study aims were to characterize deficits in skeletal muscle mass, strength and physical performance, and examine the associations of these deficits with clinical outcomes.

METHODS

Fifty LTx candidates (58% men; age, 59 ± 9 years) were prospectively evaluated for skeletal muscle deficits: muscle mass using bioelectrical impedance, quadriceps, respiratory muscle and handgrip strength, and physical performance with the Short Physical Performance Battery. Comparisons between number of muscle deficits (low muscle mass, quadriceps strength and physical performance) and 6-minute walk distance (6MWD), London Chest Activity of Daily Living Questionnaire, and quality of life were assessed using one-way analysis of variance. Associations with pretransplant and posttransplant delisting/mortality, hospital duration, and 3-month posttransplant 6MWD were evaluated using Fisher exact test and Spearman correlation.

RESULTS

Deficits in quadriceps strength (n = 27) and physical performance (n = 24) were more common than muscle mass (n = 8). LTx candidates with 2 or 3 muscle deficits (42%) compared with those without any deficits (26%) had worse 6MWD = -109 m (95% confidence interval [CI], -175 to -43), London Chest Activity of Daily Living Questionnaire = 18 (95% CI, 7-30), and St. George's Activity Domain = 12 (95% CI, 2-21). Number of muscle deficits was associated with posttransplant hospital stay (r = 0.34, P = 0.04), but not with delisting/mortality or posttransplant 6MWD.

CONCLUSIONS

Deficits in quadriceps muscle strength and physical performance are common in LTx candidates and further research is needed to assess whether modifying muscle function pretransplant can lead to improved clinical outcomes.

Clinical characteristics of Japanese candidates for lung transplant for interstitial lung disease and risk factors for early death while on the waiting list

BACKGROUND

Lung transplants have produced very favorable outcomes for patients with interstitial lung disease (ILD) in Japan. However, because of the severe donor lung shortage, patients must wait approximately 2.5 years before they can undergo transplantation and many candidates die before allocation. We reveal the clinical characteristics of Japanese patients with ILD who are candidates for lung transplants and the risk factors for early death while on the waiting list.

METHODS

We retrospectively reviewed the clinical data of patients registered in the Japan Organ Transplant Network from Okayama University Hospital who are candidates for cadaveric lung transplants for ILD between 1999 and 2015.

RESULTS

Fifty-three patients with ILD were included (24 patients with idiopathic pulmonary fibrosis and 29 others). They had severe pulmonary dysfunction and low exercise tolerability. The median waiting time for transplantation was 462 days, and 22 patients died before allocation. Patients who died before 462 days without undergoing transplantation had more severe dyspnea, shorter 6-minute walk distance (6MWD), and lower performance status than those who waited ≥462 days.

CONCLUSIONS

Japanese candidates for cadaveric lung transplants for ILD have severe pulmonary dysfunction. Severe dyspnea, short 6MWD, and low performance status are risk factors for early death while on the waiting list.

Physical activity level significantly affects the survival of patients with end-stage lung disease on a waiting list for lung transplantation

PURPOSE

Our objective was to investigate the factors predicting the survival of patients on the waiting list for lung transplantation (LT) during the waiting period, with a special emphasis on the physical activity level.

METHODS

The study included 70 patients with end-stage pulmonary disease who were on the waiting list for LT at Kyoto University Hospital. We examined the association between the baseline characteristics, including the body mass index and body composition, serum albumin, serum C-reactive protein (CRP), steroid administration, physical activity level (calculated by the food frequency questionnaire) and survival during the waiting period using Kaplan-Meier curves and Cox proportional hazard regression models.

RESULTS

A physical activity level of ≤1.2 was correlated with significantly decreased survival (1-year survival: 68 vs. 90.9%, p = 0.0089), with a hazard ratio (HR) of 2.24 (95% confidence interval (CI) 1.22-4.19, p = 0.0001). Hypo-albumin (HR 2.024, 95% CI 1.339-6.009, p = 0.004), a high level of CRP (HR 2.551, CI 1.229-4.892, p = 0.02), and the administration of steroids (HR 2.258, CI 1.907-5.032, p = 0.024) were also significant predictors of survival.

CONCLUSIONS

Low levels of physical activity during the waiting period for LT led to decreased survival times among LT candidates.