Acceptance of the dying process and other risk factors for terminal hyperactive delirium in cancer patients: a multicenter cohort subanalysis

Background: Delirium is common and distressing in palliative care, particularly near death, but evidence linking difficulty in accepting the dying process to terminal hyperactive delirium is limited. This study aimed to examine the association between difficulty in accepting the dying process and hyperactive delirium in patients receiving palliative care, while accounting for other clinical risk factors.

Methods: We performed a subanalysis of a large multicenter cohort study conducted in 23 palliative care units in Japan. Variables were selected from previous studies and extracted from the present data set. The acceptance of the dying process was assessed by the attending palliative care physician. Hyperactive delirium was defined as Memorial Delirium Assessment Scale (MDAS) item 9 of ≥2. Multivariate analysis was performed to identify associations with hyperactive delirium within the last 3 days before death.

Results: A total of 1,045 patients were included (mean age was 71.5 years, 49.9% were female). Hyperactive delirium was present in 17.8% of patients. A total of 8.3% of patients had been assessed as having difficulty in accepting the dying process. Factors associated with hyperactive delirium in the last 3 days before death were: difficulty in accepting the dying process [odds ratio (OR): 2.64, 95% confidence interval (CI): 1.60–4.30, P<0.001], Eastern Cooperative Oncology Group Performance Status (ECOG PS) ≤2 (OR: 2.11, 95% CI: 1.21–3.62, P=0.009), ECOG PS =3 (OR: 1.46, 95% CI: 1.02–2.10, P=0.041), no drowsiness (OR: 1.62, 1.03–2.64, P=0.04), oral morphine equivalent daily dose (OMEDD) ≥60 mg (OR: 1.53, 1.01–2.30, P=0.043), and males (1.46, 1.04–2.05, P=0.03).

Conclusions: Difficulty in accepting the dying process was associated with hyperactive delirium within the last 3 days of life. These exploratory findings do not establish causality; prospective studies are warranted to determine whether supportive interventions around the dying process could mitigate terminal delirium.