Using State Sequence Analysis Alongside a Cost of Illness Study: Application to the Pathway of Heart Transplant Candidates in a French Heart Transplant Center

OBJECTIVES: Heart transplantation (HT) is the standard of care in selected, eligible end-stage heart failure patients but organ shortage remains a challenge. Data on the costs associated with the medical management of patients listed for HT are lacking. A state sequence analysis (SSA) was performed alongside a cost of illness study to characterize healthcare trajectories and economic outcomes while awaiting HT.

METHODS: Adult patients listed for HT in a French heart transplant center between 2018 and 2020 were included and followed until HT, death or end of the study period (June 30, 2022), whichever came first. Direct healthcare resources were collected through computerized medical records and valued from the healthcare system perspective. Six states were predefined for the SSA: hospitalization, medical procedure, medical consultation, HT, death, waiting list. Optimal Matching was used as the dissimilarity measure of patient sequences and agglomerative hierarchical clustering using Ward’s criterion was then performed.

RESULTS: Ninety-two patients were included, with 67 (73%) undergoing HT within a median time of 2 months. Overall, the mean cost per patient was €21,324.05, with an average of 2.71 hospitalizations (main cost component). Four clusters were identified. Type 1 patients (n=43) underwent HT within 1 month, with a mean cost of €5,820.12 and 1 hospitalization. Only 4 (25%) Type 2 patients (n=16) underwent HT within 30 months, with a mean cost of €22,285.32 and 4.12 hospitalizations. Type 3 patients (n=20) underwent HT within 10 months, with a mean cost of €27,541.11 and 5 hospitalizations. Type 4 patients (n=13) died before HT within 3 months, with a mean cost of €61,858.45 and 3 hospitalizations.

CONCLUSIONS: This study highlights current issues related to access to HT and its economic consequences. The SSA helped identifying pathways that could benefit most from strategies to expand the donor’s pool and could help inform resource allocation along those pathways.