Existential distress in palliative care of cancer patients at the end of life: a systematic review

Background: The experience of existential distress, along with other forms of distress, is one of the common experiences in end-of-life patients. Therefore, the purpose of this research is to review related studies and conceptualize existential distress in palliative care of cancer patients. Methods: This study was a systematic review, which was conducted from May 1 to July 31, 1402 at Allameh Tabatabai University and search strategy was written and performed in MEDLINE, Web of Science/PubMed and Scopus databases from the beginning of 2003 to the end of 2022. The inclusion criteria included all quantitative, qualitative, mixed and review studies that focused on the experience of adult patients. Lack of access to the full text of the article and studies in non-English language, clinical trial (randomized and non-randomized), letter to the editor, case report and protocol were excluded from the list of studies. After removing duplicate articles, two research authors reviewed the studies independently according to the inclusion and exclusion criteria, and the differences between them were resolved by discussion. Results: After searching, screening and selecting articles based on inclusion and exclusion criteria, finally 22 articles were included in the study, of which three were review articles, eight were quantitative and 11 were qualitative. Terminally cancer patients experience existential distress, and the data are significant for estimating the prevalence of these symptoms, especially in the severe category. In addition to examining the prevalence of this symptom, patients have described their experience of existential distress in several categories: Feelings of loneliness and isolation (or loss of support system), relationship concerns (concerns about family, changes in relationships, and conflictual relationships), loss of control/autonomy (physical control, cognitive and emotional control), burden on others, loss of sense of continuity (loss of roles, pleasurable activities and sense of self), uncompleted life tasks, hopelessness/helplessness, dissolving of the future, uncertainty and frightening ambiguity, feeling guilt/ regret about the past, lack of meaning, inevitable thoughts of death. Conclusion: It seems that the themes raised beyond cultural differences show the universal human suffering, whose accurate conceptualization can help to develop effective therapeutic interventions to reduce existential distress.