Associations of patient–family pain-related fear beliefs with early mobilization function after thoracic surgery: the role of perceived overprotection

To examine the associations of patient and family member pain-related fear beliefs with early mobilization function after thoracic surgery, estimate the statistical indirect association involving perceived overprotection, and test the interaction between patient and family member fear beliefs. A preoperative-postoperative two-timepoint paired prospective design was adopted. A total of 180 patient-family member pairs were initially recruited from the thoracic surgery department of a tertiary hospital between March 2025 and October 2025. Fifteen patients were excluded after postoperative transfer to the ICU, leaving 165 pairs for postoperative follow-up, of which 157 with complete core variables were included in the main analysis. One day before surgery, the Fear of Pain Questionnaire-9 (FPQ-9) was administered to patients and family members. On postoperative day 3, the Tampa Scale for Kinesiophobia-11 (TSK-11), Perceived Overprotection Scale-6 (POP-6), Numeric Rating Scale (NRS), and a 2-minute walk test (2MWT) were completed. Hierarchical regression, bootstrap mediation analysis (5,000 resamples), and interaction testing were used to examine adjusted associations, statistical indirect associations, and the interaction between patient and family member FPQ-9. Patient FPQ-9 (25.64 ± 7.59) was significantly higher than Family FPQ-9 (22.69 ± 7.04, p < 0.001), and the two scores were positively correlated ( r = 0.280, p < 0.001). The TSK-11 score was 27.92 ± 4.99, with 77.1% of the patients scoring ≥ 25; 2MWT distance was 82.45 ± 31.86 m. After controlling for demographic and clinical factors, both Family FPQ-9 (B=-0.945, p = 0.005) and patient FPQ-9 (B=-1.147, p < 0.001) were independently and negatively associated with 2MWT. In the model adjusted for demographic and clinical factors, the estimated indirect association involving perceived overprotection was − 0.353 (95%CI [-0.719, -0.012]), accounting for 26.9% of the total association. After additional adjustment for patient FPQ-9, the estimated indirect association was − 0.378 (95%CI [-0.749, -0.043]). The interaction between patient and family member FPQ-9 was not significant (ΔR²=0.012, p = 0.102). Family members’ preoperative pain-related fear beliefs were associated with shorter postoperative day 3 walking distance after adjustment for patient fear beliefs and demographic and clinical factors. An exploratory statistical indirect association involving perceived overprotection was observed. The interaction between patient and family member fear beliefs was not statistically significant. The observational design and same-day assessment of perceived overprotection and walking distance preclude causal interpretation.