Incidence and associated factors of sudden unexpected death in advanced cancer patients: A multicenter prospective cohort study

Abstract Purpose A sudden unexpected death has significant negative impacts on patients, family caregivers, and medical staff in hospice/palliative care. This study aimed to clarify the incidence and associated factors of sudden unexpected death according to four definitions in advanced cancer patients. Methods We performed a prospective cohort study in 23 inpatient hospices/palliative care units in Japan. Advanced cancer patients aged ≥18 years who were admitted to inpatient hospices/palliative care units were included. The incidence and associated factors of sudden unexpected death were evaluated in all enrolled patients according to four definitions: (a) rapid decline death, defined as a sudden death preceded by functional decline over 1–2 days; (b) surprise death, defined if the primary responsible palliative care physician answered “yes” to the question, “Were you surprised by the timing of the death?”; (c) unexpected death, defined as a death that occurred earlier than the physicians had anticipated; and (d) performance status (PS)‐defined sudden death, defined as a death that occurred within 1 week of functional status assessment with an Australia‐modified Karnofsky PS ≥50. Results Among 1896 patients, the incidence of rapid decline death was the highest (30‐day cumulative incidence: 16.8%, 95% CI: 14.8–19.0%), followed by surprise death (9.6%, 8.1–11.4%), unexpected death (9.0%, 7.5–10.8%), and PS‐defined sudden death (6.4%, 5.2–8.0%). Male sex, liver metastasis, dyspnea, malignant skin lesion, and fluid retention were significantly associated with the occurrence of sudden unexpected death. Conclusion Sudden unexpected death is not uncommon even in inpatient hospices/palliative care units, with range of 6.4–16.8% according to the different definitions.