Development and Validation of an Individual Predictive Model for Risk of Biopsy-Proven Antibody-Mediated Rejection after Heart Transplantation

Purpose In contrast to acute cellular rejection, non-invasive assessment of antibody-mediated rejection (AMR) remains challenging. The routine surveillance endomyocardial biopsies (EMB) approach to monitor AMR suffers from multiple limitations. The development of an individual AMR risk score may allow for individualization of the EMB protocol. Methods We analyzed a prospective and deeply phenotyped cohort of patients transplanted between 2012 and 2017 at our center (n=700). Patients were randomly distributed in a training (2/3) and in a test set (1/3). We applied a mixed effect logistic regression with a random intercept to identify predictive variables associated with AMR ≥ pAMR1 at the level of each EMB. An AMR risk score was derived by applying the β-coefficients attributed to each predictive variable. Results A total of 6,403 EMB were analyzed among which 412 (6.4%) were diagnosed as AMR ≥ pAMR 1. In the training set, five predictive variables were independently associated with AMR: time post-transplant (p Conclusion We identified 5 independent predictive variables associated with AMR and derived an AMR risk score that may help clinicians in individualizing the EMB protocol.