Expression of inflammatory states in response to psychological distress in breast cancer survivors and its relationship to subjective memory function complaints.

Abstract

Background: Breast cancer (BC) survivors frequently endure psychological distress following chemotherapy, with subjective memory decline being a prevalent aspect of chemotherapy-related cognitive impairment (CRCI). This study aimed to assess the influence of psychological distress on subjective memory decline in BC survivors with CRCI and investigate potential underlying mechanisms.

Methods: A total of 104 BC survivors who had completed chemotherapy were categorized based on the distress thermometer (DT) score into a no-psychological distress group (NPD group, n = 51) and a psychological distress group (PD group, n = 53). The groups were compared using the Mini-Mental State Examination (MMSE), the Prospective and Retrospective Memory (PM and RM) Questionnaire (PRMQ), cytokine levels (of interleukin-1β [IL-1β], tumor necrosis factor-alpha [TNF-α], and IL-4), and inflammatory markers (neutrophil-to- lymphocyte ratio [NLR], platelet-to-lymphocyte ratio [PLR], monocyte count-to-lymphocyte ratio [MLR], granulocyte-to-lymphocyte ratio [GLR], and systemic immune-inflammation index [SII]). Mediation analysis was performed to explore whether cytokine and inflammatory marker levels mediate the effect of psychological distress on subjective memory function complaints.

Results: The NPD group performed significantly better in the PD group both RM (z = -3.370, p = 0.001) and PM (z = -1.967, p = 0.049). The IL-1β levels were substantially higher in the PD group than in the NPD group (z = -2.920, p = 0.004). Similarly, NLR (z = -2.585, p = 0.010), GLR (z = -2.858, p = 0.004), and SII (z = -2.747, p = 0.006) were higher in the PD group. Mediation analysis revealed that IL-1β partially mediated the relationship between DT and RM (β = 0.019, p = 0.007), while SII fully mediated the relationship between DT and PM (β = 0.003, p = 0.017).

Conclusion: BC survivors experiencing psychological distress exhibited worse subjective memory and elevated levels of IL-1β, NLR, GLR, and SII. These findings suggest that inflammation may be a cause of subjective memory function complaints in BC survivors with psychological distress.