Effects of Acceptance and Commitment Therapy on health-related outcomes for patients with advanced cancer: A systematic review

Background: Advanced cancer is an incurable and life-threatening disease that poses a major challenge to patients' psychological and physical well-being. Acceptance and Commitment Therapy is a mindfulness-based behavioural therapy for managing health outcomes and inducing health-related behaviour changes. However, the components and modality of Acceptance and Commitment Therapy and its effectiveness on health outcomes for patients with advanced cancer remain unclear. Objectives: This review aimed to identify the main content, delivery mode, dosage and duration of Acceptance and Commitment Therapy, and to systematically summarise evidence regarding its application in patients with advanced cancer for improving physical and psychological outcomes and health-related quality of life. Design: Systematic review. Data sources: PubMed, British Nursing Index, Medline, PsycINFO, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure and WANFANG Data were searched to identify eligible clinical trials. Review methods: Two reviewers independently assessed the eligibility of each study and extracted data. The Joanna Briggs Institute critical appraisal checklist was used to evaluate the risk of bias in the included studies. Narrative synthesis was used to present the findings of this review. Results: Six studies involving 261 participants were included in this review, including five randomised control trials and one with a pretest-posttest design. Two out of the five studies reported Acceptance and Commitment Therapy significantly reduced depressive symptoms and psychological distress post-intervention with a large effect size compared with usual care. One study indicated significant improvements in anxiety, sleep characteristics and health-related quality of life with a large effect size post-intervention. Non-significant changes in fatigue and pain were found. Intervention programmes with no more than four sessions had high adherence rates. Conclusion: Acceptance and Commitment Therapy may be a beneficial way to improve depressive symptoms, anxiety, psychological distress, sleep characteristics and health-related quality of life in patients with advanced cancer. However, limited studies, small sample size and methodological heterogeneity weaken the evidence. More rigorous research using brief Acceptance and Commitment Therapy programmes should be conducted within larger samples to further confirm the effectiveness and evaluate its long-term effect on this population. (c) 2021 Elsevier Ltd. All rights reserved.