Composite risk scores and depression as predictors of competing waiting-list outcomes: the Waiting for a New Heart Study

We evaluated two composite risk scores, (Heart Failure Survival Score, HFSS; German Transplant Society Score, GTSS), and depression as predictors of mortality and competing waiting-list outcomes [high-urgency transplantation (HU-HTx), elective transplantation, delisting because of clinical improvement] in 318 heart transplant (HTx) candidates (18% women; aged 53 ± 11 years) from 17 hospitals and newly registered with Eurotransplant. Demographic variables and depression (Hospital Anxiety and Depression Scale, HADS) were assessed using questionnaires. Variables to compute HFSS and GTSS, age, medications, and outcomes were provided by Eurotransplant. At 12 months, 33 patients died, 83 received urgent HTx, 30 elective HTx, and 17 were delisted because of improvement. Applying cause-specific Cox regressions, only the HFSS was significantly associated with 1-year mortality [HR = 0.64 (95% CI = 0.43-0.95), P = 0.029]. The GTSS was the strongest predictor of HU-HTx [HR= 1.02 (95% CI = 1.01-1.02), P < 0.001]. Low depression scores contributed significantly to clinical improvement, even after adjusting for age and risk scores [HADS: HR = 0.12 (95% CI = 0.02-0.89), P = 0.039]. These findings confirm the usefulness of composite risk scores for the prediction of mortality and HU-HTx, validating both scores for their intended use. The finding that depression was an independent predictor of the waiting-list outcome clinical improvement suggests that considering patients' psychological attributes in addition to their medical characteristics is advisable.