Exploring Loneliness, Social Factors, and Clinical Correlates of C-reactive Protein in African American Breast Cancer Survivors.

IMPORTANCE

African American women experience disproportionately high breast cancer morbidity and mortality, including early 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 altering immune signaling within the tumor microenvironment. However, few studies have examined how stress-related psychosocial factors, such as loneliness, contribute to inflammatory processes in African American breast cancer survivors.

OBJECTIVE

To examine the association between loneliness and other social, socioeconomic, and clinical factors with C-Reactive Protein (CRP) levels, an established marker of systemic inflammation, in African American breast cancer survivors.

DESIGN

Exploratory pilot, cross-sectional study.

SETTING

NCI-designated Cancer Center.

PARTICIPANTS

African American women (n = 61) diagnosed with Stage I-IIIa breast cancer who completed the UCLA Loneliness Scale and provided blood samples that were used to measure CRP as part of a laboratory-based study of stress reactivity.

MAIN OUTCOMES AND MEASURES: The primary outcome was CRP level (mg/L), and the primary predictor was the total score on the 3-item UCLA Loneliness Scale. Linear regression models were used to examine the association between loneliness and log-transformed CRP levels, adjusting for age, body mass index (BMI), financial strain, multimorbidity status, employment, and marital status.

CONCLUSIONS AND RELEVANCE: In this exploratory pilot study, loneliness was not significantly associated with CRP levels in African American breast cancer survivors. However, significant associations were observed between CRP levels and financial strain, multimorbidity status, and higher BMI. These findings underscore the need for greater conceptual clarity in distinguishing the components of social disconnection in relation to the inflammatory processes. Interventions addressing financial hardship, obesity, and multimorbidity management in survivorship care may help mitigate chronic inflammation and improve long-term health outcomes in a population that continues to experience breast cancer disparities.