Selecting lung transplant candidates: where do current guidelines fall short?

Abstract

In 2010, 1770 lung transplant procedures were performed in the USA, yet 2469 new candidates were added to the waiting list the same year. The shortage of suitable donor lungs requires that transplant professionals select patients for lung transplantation only if they are likely to sustain a survival benefit from the procedure. However, 20% of lung transplant recipients die within the first year of transplantation, suggesting that we are failing to identify those at high risk for severe early complications. In this perspective, we review the current guidelines for the selection of lung transplant candidates, which are based largely on expert opinion and small case series. We also propose the study of new extrapulmonary factors, such as frailty and sarcopenia, that might help improve the prediction of complications and early death after lung transplantation, leading to an improved candidate selection process.

Figure 1. Temporal trends in recipient age at the time of lung transplantation in the USA

Data taken from [101].

Figure 2. Continuous relationships between BMI and risk of death at 1 year and at 5 years conditional on 1-year survival after lung transplantation

Solid lines = multivariable-adjusted smoothed regression lines. Dotted lines = 95% CI. In (A), both nonlinear (p = 0.02) and linear (p = 0.02) relationships were statistically significant. In (B), the nonlinear (p = 0.04), but not the linear (p = 0.35), relationship was statistically significant. The significant p-values for the smoothed (nonlinear) curves suggest that the relationship between BMI and risk of death after lung transplantation is nonlinear, with higher early and late mortality rates for both underweight and obese recipients. The wide confidence intervals at the extremes of BMI are due to smaller numbers of transplant recipients with these values. Reprinted from [52] with permission of the American Thoracic Society. © American Thoracic Society.

Figure 3. Continuous association between BMI and grade 3 primary graft dysfunction adjusted for diagnosis, cardiopulmonary bypass and transplant procedure type

Solid line shows the effect estimate; dotted lines show the 95% CI bands. The p-value is for the association between BMI and PGD. PGD: Primary graft dysfunction. Reprinted from [53] with permission of the American Thoracic Society. © American Thoracic Society.

Figure 4. Survival effect of double lung transplantation in patients with chronic obstructive pulmonary disease according to values of prognostic variables

The survival effect of lung transplantation is defined as the difference between the expected median survival with lung transplantation and that without lung transplantation. The survival benefit is divided into gain of 1 year or more (black), loss of 1 year or more (white) and gain or loss of less than 1 year (gray). The dashed line separates between gain and loss of survival. FEV₁: Forced expiratory volume in 1 s. Reprinted from [80] with permission of the American Thoracic Society. © American Thoracic Society.