Impact of lung allocation score on survival in cystic fibrosis lung transplant recipients

BACKGROUND

The lung allocation score (LAS) has changed organ allocation for lung transplantation in the United States. Previous investigations of transplant recipients reported an association between high LAS and an increased risk of death after lung transplantation. We hypothesize that a high LAS predicts survival in lung transplant recipients with cystic fibrosis (CF) in the United Network for Organ Sharing Scientific Registry of Transplant Recipients database.

METHODS

A cohort study was conducted of 1,437 U.S. adult lung transplant recipients with CF from May 1, 2005, through December 31, 2012. The cohort was divided into a high-risk group and a low-risk group based on LAS. Survival data were examined using Kaplan-Meier estimates and Cox proportional hazard models to compare survival. The primary outcome was adjusted survival at 1 year after lung transplantation.

RESULTS

The high-risk group of 318 patients with a median LAS of 69.6 (interquartile range 56.3-87.2) was compared with a low-risk group of 1,119 patients with a median LAS of 38.8 (interquartile range 36.3-42.3). Patients in the high-risk group had a 41% increased relative risk of cumulative mortality at 1 year after transplantation compared with the low-risk group (16.1% vs 12.0%). After adjustment for known predictors of mortality, the risk of death at 1 year after transplantation remained elevated (hazard ratio = 1.41; 95% confidence interval = 1.00-2.01). The high-risk group had worse survival at 90 days and 2 years after lung transplantation.

CONCLUSIONS

High LAS are associated with worse survival in lung transplant recipients with CF.

Role of Physical Performance Assessments and Need for a Standardized Protocol for Selection of Older Kidney Transplant Candidates

The older adult population (65 years or older) with advanced or end-stage kidney disease is steadily growing, but rates of transplantation within this cohort have not increased in a similar fashion. Physical deconditioning, resulting in poor post-transplantation outcomes, is a primary concern among older renal patients. The assessment of physical function often holds more weight in the selection process for older candidates, despite evidence showing benefits of transplantation to this vulnerable population. Although several frailty assessment tools are being used increasingly to assess functional status, there is no standardized selection process for older candidates based on these assessment results. Also, it is unknown if timely targeted physical therapy interventions in older patients result in significant improvement of functioning capacity, translating to higher listing and transplantation rates, and improved post-transplantation outcomes. It is therefore of upmost importance not only to incorporate an effective objective functional status assessment process into selection and waitlist evaluation protocols, but also to have targeted interventions in place to maintain and improve physical conditioning among older renal patients. This paper reviews the commonly utilized assessment tools, and their applicability to older patients with renal disease. We also propose the need for definitive selection and waitlist management guidelines to formulate a streamlined assessment of functional capacity and transplant eligibility, as well as a process to maintain functional status, thereby increasing the access of older patients to renal transplantation.