Abstract A025: Exploring loneliness and other social and clinical predictors of c-reactive protein in African American breast cancer survivors

Abstract Importance: African American (AA) women experience disproportionately high breast cancer morbidity and mortality, including earlier onset, more aggressive tumor subtypes, and poorer survival outcomes. Chronic psychosocial stress has been shown to dysregulate hypothalamic–pituitary–adrenal axis and sympathetic nervous system activity, promoting low-grade systemic inflammation and altered immune signaling within the tumor microenvironment. However, few studies have examined how stress-related psychosocial factors such as loneliness may contribute to inflammatory processes among AA breast cancer survivors. Objective: To examine the association between loneliness and other social, socioeconomic, and clinical factors with levels of C-Reactive Protein (CRP), an established marker of systemic inflammation, in AA breast cancer survivors. Design: Cross-sectional study. Setting: NCI-designated cancer center. Participants: AA women (n=61) diagnosed with Stage I–IIIa breast cancer who completed the UCLA Loneliness Scale and provided blood samples for CRP measurement at the pre-challenge laboratory visit. Main outcomes and Measures: The primary outcome was CRP level (mg/L), and the primary predictor was total score on the 3-item UCLA Loneliness Scale. Linear regression models were used to examine the association between loneliness and CRP, adjusting for age, BMI, financial strain, comorbidity status, employment, and marital status. Conclusions and Relevance: Loneliness was not significantly associated with CRP levels in this sample of AA breast cancer survivors, consistent with prior research exploring associations between loneliness and CRP. This study adds to the literature by examining these associations in a historically underrepresented population that is at increased risk for psychosocial stress and adverse health outcomes. These findings underscore the need for greater conceptual clarity in distinguishing and measuring components of social disconnection (specifically loneliness, social isolation, and social support) in relation to inflammatory processes. Significant associations were observed between CRP and financial strain, comorbidity status, and higher BMI. Interventions targeting financial hardship, obesity, and comorbidity management in survivorship care may help mitigate chronic inflammation and improve long-term health outcomes in this population. Future studies should incorporate both subjective and objective indicators of psychosocial stress to clarify their biological relevance and inform strategies to reduce cancer health disparities. Citation Format: Kelsie Campbell, Fatimata Sanogo, Trista Beard, Chanita Hughes Halbert, Melanie Jefferson. Exploring loneliness and other social and clinical predictors of c-reactive protein in African American breast cancer survivors abstract. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr A025.