Due to medical progress and an aging population, the number of patients and caregivers who face the profound existential challenges of advanced incurable cancer is constantly growing. Clinically significant existential distress may result from a fear of suffering and perceived lack of control, fear and uncertainty about the end of life, feelings of burdensomeness or insufficiency, grief about missed opportunities, and profound loneliness. Such distress may have a unique and independent contribution to health care outcomes at the end of life. Despite an increasing interest in existential and palliative care interventions that discuss such issues openly, a lack of systematic quantitative data on existential distress and specific support needs hampers clinicians to consequently detect and address existential needs. This longitudinal study aims to 1) systematically investigate the frequency, longitudinal trajectory and predictive impact of existential distress on patient- and caregiver-relevant end-of-life outcomes and 2) determine patients' and caregivers' specific need for and utilization of psychosocial support with respect to existential concerns.~Adult patients diagnosed with advanced cancer and caregivers will be consecutively recruited from outpatient and inpatient treatment facilities of the Univer-sity Cancer Center Hamburg and affiliated clinics. Existential distress, end-of-life outcomes, and mental disorders in 1,000 participants (500 patients, 500 care-givers) will be assessed using self-report questionnaires at five points of assessment over a period of 12 months and diagnostic interviews (at baseline, after six months). To determine the prevalence of existential distress, mental disorders and palliative care outcomes descriptive statistics will be calculated. Descriptive analyses will also be used to examine the need for and utilization of psychosocial support. To investigate the predictive impact of existential distress and patient- and caregiver-relevant end-of-life outcomes multiple linear and logistic regression will be conducted. To analyze longitudinal trajectory of existential distress growth mixture models will be used.~Shaping a clear and systematic knowledge about frequent and persistent existential concerns that are most relevant to the risk for unfavorable end-of-life outcomes, results will significantly contribute to the recognition and manage-ment of existential distress and provide a valuable basis for the development of targeted interventions.
Despite the potential for alleviation of existential distress through psychosocial interventions, existential concerns and their impact on health care outcomes of patients and caregivers have not yet been systematically studied. The aim of this longitudinal cohort study is to investigate the frequency, longitudinal trajectory and predictive impact of existential distress on patient- and caregiver-relevant end-of-life outcomes. Further, it aims to determine the need for and utilization of psychosocial support in patients and caregivers with regard to existential concerns.