Abstract PS3-03-30: Association between allostatic load and clinical and sociodemographic risk factors for breast cancer among diverse women undergoing screening mammography

Abstract Introduction: Allostatic load (AL) is an index that accounts for cumulative stress on the body and is associated with increased breast cancer risk and breast cancer mortality. We aimed to determine the association between demographic, clinical and lifestyle factors and AL among women undergoing screening mammography. Methods: Patients were enrolled in the Electronic Medical Records and Genomics (eMERGE4) study at Columbia University Irving Medical Center and completed surveys on demographic, clinical and lifestyle factors, provided samples for germline BRCA1/2 and PALB2 genetic testing and polygenic risk score (PRS) for breast cancer (308-SNP model), and allowed access to electronic medical record (EMR) data. Women with at least one screening mammogram were included. To calculate AL score, we extracted the most recent EMR data on 9 biometrics representing major regulatory systems: cardiovascular (pulse, systolic and diastolic blood pressure), metabolic (albumin, alkaline phosphatase, glucose), renal (blood urea nitrogen, creatinine), and immune (white blood cells). One point was assigned to each biometric in the highest quartile except albumin which was the lowest quartile. Patients with at least 5 biometrics were included; missing values were imputed. High AL was defined as AL score above the cohort median. Demographic, clinical, and lifestyle factors from pre-test survey data included age, race/ethnicity, highest educational level, annual household income, health insurance, disability, body mass index (BMI), smoking and alcohol use, and physical activity level. We extracted breast density (4-category BIRADS classification) and prior breast biopsy results from the EMR. Univariable and multivariable logistic regression analyses were conducted to evaluate the association between high AL and demographic, clinical, and lifestyle factors. Results: Among 955 evaluable women, the mean age was 54.8 years (standard deviation SD 11.4), with 48.2% Hispanic, 34.9% non-Hispanic White, 9.1% non-Hispanic Black, and 7.9% Asian/other. Median AL score was 2 (range, 0-8), and 418 patients had high AL. Mean BMI was 27.7 kg/m2 (SD 6.3). A total of 10.4% of the patients had a prior history of breast cancer. Most patients (61.7%) reported 0 days of vigorous exercise a week. Over half (54.6%) have a bachelor’s or advanced degree. Almost half (45.5%) of those with high AL have Medicaid versus 25.1% of those with low AL. In univariable analysis, older age, Black race, Hispanic ethnicity, higher breast cancer PRS, lower breast density, having a disability, lower educational attainment, lower income, public health insurance, higher BMI, less alcohol use, and less physical activity were associated with high AL. In multivariable analysis, older age (odds ratio OR=1.03, 95% confidence interval CI=1.02-1.05), higher BMI (OR=1.09, 95% CI=1.06-1.12), and having Medicaid vs. private health insurance (OR=2.21, 95% CI=1.30-3.75) were significantly associated with high AL score. Conclusions: In our diverse population of women undergoing screening mammography, we found a significant association between clinical, demographic, and socioeconomic factors and AL, which is a well-established breast cancer risk factor. In addition to age and BMI, having Medicaid compared to private health insurance was associated with a greater than 2-fold likelihood of having high AL. Although protective against breast cancer risk, lower breast density and less alcohol use were also associated with higher AL, warranting further investigation. These findings highlight the importance of addressing modifiable risk factors such as obesity for reducing AL and breast cancer risk and the need to address psychosocial stressors in vulnerable populations with Medicaid. Citation Format: V. Ro, J. B. Gibbons, C. N. Ta, C. Liu, W. K. Chung, C. Weng, K. D. Crew. Association between allostatic load and clinical and sociodemographic risk factors for breast cancer among diverse women undergoing screening mammography abstract. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS3-03-30.