Validating a novel score based on interaction between ACLF grade and MELD score to predict waitlist mortality

Area of Science:

• Hepatology
• Transplant Surgery
• Critical Care Medicine

Background:

• The Model for End-Stage Liver Disease (MELD) score may not fully capture the severity of acute-on-chronic liver failure (ACLF) in liver transplant candidates.
• Data on the interaction between ACLF and MELD score in predicting waitlist mortality are limited.

Purpose of the Study:

• To investigate the interaction between MELD score and ACLF grade in predicting 90-day waitlist mortality for adult liver transplant candidates with cirrhosis.
• To develop and validate a new scoring system that incorporates both MELD and ACLF for improved risk stratification.

Main Methods:

• Analysis of the UNOS database (01/2002 to 06/2018) for adult liver transplant listings with cirrhosis and ACLF.
• Utilized Fine and Gray regression to identify interactions between MELD and ACLF grade.
• Developed and validated a novel scoring system based on the interaction model.

Main Results:

• A significant interaction was found between MELD score and ACLF grade, with ACLF having a greater impact at lower MELD scores.
• Waitlist mortality increased with higher ACLF grades (21.6% overall; 18% for ACLF grade 1 to 39% for ACLF grade 3b).
• The developed scoring system effectively stratified patients into quartiles of waitlist mortality risk (13% to 36%).

Conclusions:

• MELD score and ACLF interact significantly in predicting 90-day waitlist mortality among liver transplant candidates.
• The developed scoring system demonstrates good calibration and correlation for predicting waitlist mortality.
• Further validation in prospective studies is recommended to support incorporating both MELD and ACLF in transplant prioritization.