A mortality risk score for septuagenarians undergoing orthotopic heart transplantation

Background With septuagenarians undergoing orthotopic heart transplantation (OHT) more frequently, we aimed to develop a risk score for 1-year mortality in this population. Methods Septuagenarian OHT recipients were identified from the UNOS registry between 1987 and 2018. The primary outcome was 1-year post-OHT mortality. Patients were randomly divided into derivation and validation cohorts. Associated covariates were entered into a multivariable logistic regression model. A risk score was created using the magnitudes of the odds ratios from the derivation cohort, and its 1-year post-OHT mortality prediction capacity was tested in the validation cohort. Results A total of 1156 septuagenarians were included, and they were randomly divided into derivation (66.7%, n = 771) and validation (33.3%, n = 385) cohorts. An 11-point risk score incorporating 4 variables was created, which included mechanical ventilation, serum bilirubin, serum creatinine, and donor age. The predicted 1-year mortality ranged from 4.2% (0 points) to 48.1% (11-points) (p < .001). After cross-validation, the c-index was 0.67 with a Brier score of 0.10. Risk scores above 3 points portended a survival disadvantage at 1-year follow-up (p < .001). Conclusions This 11-point risk score for septuagenarians is predictive of mortality within 1-year of OHT and has potential utilization in improving recipient evaluation and selection of elderly patients.