Perceived support and psychological resilience as collaborative mediators between external support and quality of life in elderly breast cancer patients

Both patients' psychological resilience and perceived social support significantly moderate the impact of external social support on quality of life (QoL), yet their interactive contribution remain largely unclear. This study focuses on elderly breast cancer patients, and aims to investigate how these factors individually and interactively mediate the effect of social support on QoL. A total of 143 elderly breast cancer patients were recruited in this cross-sectional study, to survey the Social Impact Scale (SIS), Perceived Social Support Scale (PSSS), Breast Cancer Resilience Scale (BCRS), and Short Form-36 Health Survey (SF-36). The independent associations between SF-36 scores with other scale dimensions were investigated in particular, both unadjusted and adjusted for adjusting for demographic characteristics. Furthermore, the individual and interactive effects of PSSS and BCRS in the relationship between SIS and SF-36 were systematically evaluated. SF-36 overall and dimensional scores exhibited generally negative correlations with SIS scores (most r≤-0.3, P < 0.001), while generally positive correlations with PSSS and BCRS scores (most r ≥ 0.3, P < 0.001). Before adjusting for demographic characteristics, SIS3-social isolation dimensional score demonstrated negatively independent association with SF-36 overall and dimensional scores (β=-0.82~-13.50, all P < 0.05), whereas BCRS1-personal protection dimensional score demonstrated positively independent associations with SF-36 overall score and its "general health", "vitality", and "mental health" dimensional scores (β = 0.64 ~ 5.74, all P < 0.05), and PSSS1-family support score demonstrated positively independent associations with SF-36 "social function" and "mental health" dimensional scores (β = 0.93 and 1.27, both P < 0.05). The independent association analysis incorporating demographic characteristics revealed prediction roles of BCRS1-personal protection, SIS3-social isolation, patient age, and disease duration on the SF-36 overall score (all P < 0.05). Finally, our mediating effect model revealed that neither PSSS nor BCRS alone significantly mitigated the effect of SIS on SF-36 (both P > 0.05). Instead, PSSS mitigated this effect by enhancing BCRS, contributing 8.39% in total effect (P < 0.05). Our findings suggest that patients' perception of external social support improves their QoL by enhancing their resilience. Notably, external social isolation press and patients' personal protection psychology are closely associated with their overall QoL.