Predicting unplanned hospital readmission in palliative outpatients (PRePP) – study protocol of a longitudinal, prospective study to identify informal caregiver-related and structural predictors

BACKGROUND: Although the majority of German patients in a palliative state prefer to die at home, the actual place of death is most often a hospital. Unplanned hospital readmissions (UHA) not only contradict most patients’ preferences but also increase the probability of an aggressive end-of-life treatment. As limited knowledge is available which factors contribute to an UHA, the PRePP-project aims to explore predictors related to informal caregivers (IC) as well as medical and structural factors. METHODS: This prospective, observational, mono-centric study will assess structural and medical factors as well as ICs’ psychological burden throughout seven study visits. Starting in April 2021 it will consecutively include 240 patients and their respective IC if available. Standardized measures concerning ICs’ Quality of Life (WHOQOL-BREF), psychological distress (NCCN-Distress Thermometer), anxiety (GAD-7) and depressiveness (PHQ-9) will be assessed. If participants prefer, assessment via phone, browser-based or paper-based will be conducted. Medical records will provide routinely assessed information concerning patient-related characteristics such as gender, age, duration of hospital stay and medical condition. Nurse-reported data will give information on whether hospitalization and death occurred unexpectedly. Data will be progressed pseudonymized. Multivariable regression models will help to identify predictors of the primary endpoint “unplanned hospital admissions”. DISCUSSION: The PRePP-project is an important prerequisite for a clinical risk assessment of UHAs. Nevertheless, it faces several methodological challenges: as it is a single center study, representativity of results is limited while social desirability might be increased as the study is partly conducted by the treatment team. Furthermore, we anticipated an underrepresentation of highly burdened participants as they might refrain from participation. TRIAL REGISTRATION: This study was retrospectively registered 19 October 2021 at clinicaltrials.gov (NCT05082389). https://clinicaltrials.gov/ct2/show/NCT05082389