Family Caregiver Burden in Breast Cancer Patients from the Perspective of Dyadic Illness Management: A Scoping Review

Background: Family caregivers of patients with breast cancer commonly face considerable physical, psychological, and economic burden. Existing studies have mostly adopted a single caregiver perspective and lack a systematic synthesis of assessment tools, influencing factors, and intervention strategies. Objective: To systematically synthesize the assessment tools, influencing factors, and intervention strategies for caregiving burden among family caregivers of patients with breast cancer using a scoping review approach, and to identify current knowledge limitations and future directions based on Dyadic Illness Management Theory (DIMT). Methods: Guided by the JBI scoping review methodological framework and the PRISMA-ScR reporting guideline, nine Chinese and English databases were systematically searched from inception to May 8, 2026. Two researchers independently conducted literature screening and data extraction. The assessment tools, influencing factors, and interventions in the included studies were descriptively categorized and synthesized. Results: A total of 28 studies were included, of which 17 were cross-sectional studies. Regarding assessment tools, generic scales represented by ZBI were the most widely used, but none contained measurement items specific to breast cancer–specific care contexts such as postoperative body image changes and lymphedema management. In the included studies, apart from ZBI, no other burden scale had undergone specific reliability and validity validation in the breast cancer caregiver population, which may underestimate the true burden of this group. Regarding influencing factors, poor patient self-care ability and severe negative emotions, as well as caregiver sleep insufficiency and passive coping, were important factors aggravating caregiving burden. In addition, conclusions regarding the effects of age and sex on burden were inconsistent across studies. Regarding interventions, family dignity intervention and mindfulness-based stress reduction (MBSR) could reduce caregiver burden in the short term, but long-term follow-up data were lacking, and few studies simultaneously targeted both patients and caregivers as intervention recipients. Conclusion: This study found that current assessment tools for caregiving burden among breast cancer caregivers generally lack disease specificity and breast cancer population-specific validation; influencing factors involve not only the physical and mental status of patients and caregivers but are also affected by traditional Chinese culture; existing interventions are mostly short-term and single-perspective studies. Future efforts are urgently needed to develop or validate assessment tools covering specific items such as postoperative body image changes; clinical assessment should attend to the deep influence of cultural background on caregivers. In addition, it is recommended that DIMT be used to treat patients and caregivers as a whole and to conduct multicenter, long-term follow-up dyadic intervention studies, so as to develop intervention programs more aligned with Chinese family cultural contexts.