Model for end-stage liver disease dynamic stratification of survival benefit.

ABSTRACT

Only patients with Model for End-stage Liver Disease (MELD) scores ≥18 or ≥17 experience a survival benefit (SB) at 12 and 36 months after liver transplantation (OLT). The SB calculation estimates the difference after stratification for risk categories between the survival rate of transplanted versus waiting list patients. The aim of this study was to perform a short- and long-term (60 months) SB analyses of a Italian OLT program. One-hundred seventy-one patients were stratified into four MELD classes (6-14, 15-18, 19-25, 26-40), and two groups namely, waiting list (WL) and transplanted groups (TX). The median waiting time for transplanted patients was 4.4 months (range, 0-35). SB was expressed as mortality hazard ratio (MHR) as obtained through a Cox regression analysis using as a covariate the status of each patient in the waiting list (WL = 0, reference group) or the TX group (TX = 1). Values over 1 indicated the MHR in favor of the WL with the values below 1 indicating MHR in favor of Tx. In the MELD class 6 to 14, the MHR was above 1 at 3 and 6 months, indicating an SB in favor of WL; subsequently, the MHR dropped below 1, indicating an SB in favor of TX (P < .05). In the MELD class 15 to 18 the MHR was above 1 at 3 months, but below 1 subsequently (P < .05). For MELD classes 19 to 25 and 26 to 40, the MHR was always below 1 (P < .01). According to the SB approach, patients in the MELD class 6 to 14 could safely wait for at least 36 months; patients in the MELD class 15 to 18 should likely remain no longer than 12 months on the waiting list, and all the remaining patients with MELD > 18 should be transplanted as soon as possible. OLT should not be precluded but only postponed for MELD < 19 patients.