Delirium severity trajectories and survival outcome in palliative care patients

The delirium severity trajectories have been reported to be associated with poor prognosis. However, the evidence remains limited, and no studies have addressed this issue in palliative care. This study aimed to identify distinct delirium severity trajectories in palliative care patients and explore their associations with survival outcomes.

This was a longitudinal prospective cohort study conducted in the palliative care unit of the West China Fourth Hospital, Sichuan University, from February 2021 to December 2022. Advanced cancer patients who developed delirium after admission to the inpatient palliative care unit were included. The Memorial Delirium Assessment Scale (MDAS) was administered twice weekly to assess delirium severity, and group-based trajectory modeling was used to identify delirium severity trajectory subgroups. The Cox proportional hazards regression model was used to compare survival between different delirium trajectory subgroups.

A total of 213 patients with 619 MDAS assessments were analyzed in the study. Three delirium trajectories were identified as the optimal model, comprising mild-worsening, severe-worsening, and severe-remission. In the Cox proportional hazards analyses, patients in the mild-worsening group had a 2.016-fold increased risk of death (95% CI 1.038-3.916, P = 0.038), while those in the severe-worsening group had a 2.574-fold higher risk (95% CI 1.347-4.917, P = 0.004) compared with the severe-remission group. After adjusting for eight covariates, patients in the severe-worsening group remained at a significantly higher risk of death compared to those in the severe-remission group (HR 3.006, 95% CI 1.449-6.236, P = 0.003), whereas the mild-worsening group showed no significant difference (P = 0.216).

This study identified three distinct trajectories of delirium severity over time in palliative care patients, with the severe-worsening group showing the poorest prognosis. These findings could provide valuable insights for prognostic assessment and facilitate precision delirium management in palliative care settings.