The regulation mechanism of perceived stress on cognitive function of patients with breast cancer undergoing chemotherapy: a multiple mediation analysis

AimCancer-related cognitive impairment (CRCI) is one of the severe side effects affecting the quality of life of breast cancer (BC) patients. However, the mechanisms underlying CRCI are still unclear. The study aimed to examine the multiple mediating roles of resilience, social support, cortisol, and neutrophil-lymphocyte ratio (NLR) in the relationship between perceived stress and cognitive function.DesignThe study was a descriptive, cross-sectional study.MethodsThe study investigated 450 BC patients with chemotherapy in China. Convenience sampling was conducted from February to August 2023. The study used the Perceived Stress Scale, the Connor-Davidson Resilience Scale, the Social Support Rating Scale, the Functional Assessment of Cancer Therapy-Cognitive Function, the Montreal Cognitive Assessment, salivary cortisol, and NLR. SPSS 25.0 and AMOS 26.0 conducted bivariate correlations and multiple mediation analysis.ResultsThe correlations of magnitude variables ranged from no correlation to moderate level (r = - 0.002 to - 0.617). The multiple mediation path demonstrated that resilience and morning cortisol levels mediated the relationship between perceived stress and cognitive function, with a 95% confidence interval (CI) not including 0 for the direct, indirect, and total effects.ConclusionsThe study confirmed that when BC patients endure physical and psychological stress during diagnosis and treatment, individuals' resilience can buffer the stress on cognitive function. Morning salivary cortisol levels, as the product and indicator of the hypothalamic-pituitary-adrenal (HPA) axis function, may play a significant role in the effect of perceived stress on cognitive function while incapable of finding NLR as the marker of individuals' immune inflammatory response and social support play a role in this relationship. The study, based on a stress perspective, explored the regulatory mechanisms by which perceived stress affects cognitive function in patients undergoing chemotherapy for breast cancer, providing intervenable targets for subsequent improvement of patients' cognitive function.