Evaluation of Emotional Distress in Oncology Palliative Patients: Edmonton Symptom Assessment System (ESAS) and Palliative Outcome Scale (POS)—A Portuguese Cross-Sectional Study

Introduction: Cancer patients in palliative care frequently experience psychological distress, encompassing cognitive, behavioral, and emotional dimensions. This distress can significantly affect their capacity to accept the inevitability of death. Commonly, such distress manifests as sadness, depression, anxiety, and fear, which may culminate in an existential crisis. Objectives: The purpose of this study was to analyze the psychometric properties of the Edmonton Symptom Assessment System (ESAS) and the Palliative Outcome Scale (POS) among hospitalized cancer patients receiving palliative care in a Portuguese palliative care unit. Methods: Data were collected from psychological screening instruments (ESAS and POS) used in oncology patients admitted to an oncology palliative service. The study period spanned from January 2021 to March 2021. Results: The study included a convenience sample of 60 patients diagnosed with advanced cancer who were sequentially admitted to a palliative care unit. The most frequently reported primary oncological diagnoses were gastrointestinal (41.7%) and head/neck (20%) tumors. The majority of the patients were male (n = 37; 61.7%), with a median age of 72 years (range: 43–94 years). Key findings from the analysis indicated the following associations: anxiety and self-reported symptoms (higher levels of patient anxiety related to illness or treatment were strongly correlated with increased self-reported anxiety (p < 0.01)); emotional sharing and perceived meaning of life (patients who shared their feelings less frequently with family and friends were significantly less likely to find meaning in life (p < 0.01) and were more likely to report a poorer self-perception (p < 0.05)); understanding the importance of life and self-perception (a diminished understanding of the importance of life was associated with worsened self-perception (p < 0.01)); anxiety and depressive symptoms (greater anxiety related to the disease or its treatment correlated with an increased severity of depressive symptoms (p < 0.01)). Discussion and conclusion: There are numerous validated instruments available for measuring emotional distress. Among these, the ESAS and POS complement each other as practical and easy-to-use tools for evaluating emotional distress in patients admitted to palliative care settings. Findings revealed that anxiety and concerns related to the disease and its treatment, as measured by the POS, served as predictors of the risk for self-reported anxiety and depression identified by the ESAS. Furthermore, the items within the POS that evaluate the emotional component demonstrated strong internal correlation, supporting their combined use for a comprehensive assessment of this dimension.