Meta-Analysis of Randomized Controlled Trials on Yoga, Psychosocial, and Mindfulness-Based Interventions for Cancer-Related Fatigue: What Intervention Characteristics Are Related to Higher Efficacy?

SIMPLE SUMMARY: Many individuals with cancer suffer from persistent exhaustion due to cancer therapy, known as cancer-related fatigue (CRF). Yoga, psychosocial, and mindfulness-based interventions are recommended to reduce CRF. However, it is not clear yet how interventions need to be designed to maximize their efficacy. This meta-analysis aimed to identify intervention characteristics associated with greater reductions in CRF. A total of 70 interventions with 6387 participants were included in the analysis. Our results found a positive effect of yoga, psychosocial, and mindfulness-based interventions, while all invention types revealed large differences in intervention effects. In psychosocial interventions, using a group setting and working on cognition was related to higher efficacy. Regarding yoga and mindfulness-based interventions, no specific intervention characteristics emerged as more favorable than others. Overall, this meta-analysis suggests opportunities to optimize psychosocial interventions for CRF, whereas the design of yoga and mindfulness-based interventions seems to allow for variation. ABSTRACT: Cancer-related fatigue (CRF) is a burdensome sequela of cancer treatments. Besides exercise, recommended therapies for CRF include yoga, psychosocial, and mindfulness-based interventions. However, interventions conducted vary widely, and not all show a significant effect. This meta-analysis aimed to explore intervention characteristics related to greater reductions in CRF. We included randomized controlled trials published before October 2021. Standardized mean differences were used to assess intervention efficacy for CRF and multimodel inference to explore intervention characteristics associated with higher efficacy. For the meta-analysis, we included 70 interventions (24 yoga interventions, 31 psychosocial interventions, and 15 mindfulness-based interventions) with 6387 participants. The results showed a significant effect of yoga, psychosocial, and mindfulness-based interventions on CRF but with high heterogeneity between studies. For yoga and mindfulness-based interventions, no particular intervention characteristic was identified to be advantageous for reducing CRF. Regarding psychosocial interventions, a group setting and work on cognition were related to higher intervention effects on CRF. The results of this meta-analysis suggest options to maximize the intervention effects of psychosocial interventions for CRF. The effects of yoga and mindfulness-based interventions for CRF appear to be independent of their design, although the limited number of studies points to the need for further research.