The association between uncertainty in illness and fear of cancer recurrence or progression in breast cancer patients: the parallel mediating roles of coping styles and the moderating role of perceived social support.

PURPOSE: This study aimed to examine the association between uncertainty in illness (UII) and fear of cancer recurrence or progression (FCRP) in breast cancer patients, whether three coping dimensions statistically accounted for this association, and whether perceived social support moderated specific associations in the model. METHODS: A cross-sectional survey was conducted with 325 breast cancer patients from a tertiary hospital in China. Participants completed measures of UII, FCRP, coping styles, and perceived social support. Parallel mediation and moderated mediation models were estimated using Mplus 8.3 with 10,000 bootstrap resamples. Age, marital status, occupation, educational level, and cancer stage were included as covariates. RESULTS: UII was positively associated with FCRP after controlling for covariates (B = 0.447, P < 0.001). Among the three coping dimensions examined simultaneously, only the specific indirect association through acceptance-resignation coping was statistically supported (B = 0.096, 95% CI = 0.056, 0.148). Perceived social support moderated the associations of UII with confrontation coping (B = 0.004, P < 0.001), acceptance-resignation coping (B =  - 0.001, P = 0.014), and FCRP (B =  - 0.006, P = 0.024), as well as the association between acceptance-resignation coping and FCRP (B = 0.034, P < 0.001). The conditional indirect association through acceptance-resignation coping was supported at the mean and high levels of perceived social support but not at the low level; however, only the mean-versus-low contrast was statistically supported. CONCLUSION: Higher UII was associated with higher FCRP, and acceptance-resignation coping statistically accounted for part of this association. Higher perceived social support was associated with weaker associations of UII with confrontation and acceptance-resignation coping, whereas the association between acceptance-resignation coping and FCRP was stronger at higher levels of perceived social support. These findings highlight the importance of considering UII, coping dimensions, and perceived social support together when examining FCRP in breast cancer patients.