Abstract PS10-04: Identifying Risk Factors for High Allostatic Load in a Racially/Ethnically Diverse Cohort of Breast Cancer Patients

Abstract Introduction: Allostatic load (AL), an indicator of cumulative physiological stress and neuroendocrine dysregulation in response to chronic environmental challenge, has been associated with breast cancer (BC) incidence and mortality. Prior studies have found a 1.5-1.8-fold relative increase in all-cause mortality among BC patients with higher AL. Our objective was to determine whether demographic, clinical, and lifestyle factors are associated with AL in a diverse cohort of BC patients. Methods: Patients diagnosed with stage 0-IV breast cancer between 2007-2023 at Columbia University Irving Medical Center (CUIMC) in New York, NY were consented to complete a survey on demographic, clinical and lifestyle factors and allow access to their electronic health record (EHR) for research purposes. To calculate AL score, we extracted EHR data on systolic/diastolic blood pressure, heart rate, and laboratory results (albumin, alkaline phosphatase, BUN, creatinine, glucose, white blood cells). AL was calculated by assigning one point for each of 9 diagnostic biometrics exceeding the reference range. Patients were dichotomized into “high” and “low” AL groups based on the median score. Descriptive statistics, univariate and multivariate logistic regression analyses were conducted to estimate odds ratios (OR) and 95% confidence intervals (CI) for the associations between demographic, clinical and lifestyle factors with the main outcome of high AL. Results: Among 1730 evaluable patients, median age at diagnosis was 57 years (IQR: 47, 67) and 37.8% self-identified as non-Hispanic White (NHW), 12.8% non-Hispanic Black (NHB), 35.8% Hispanic, and 8.1% Asian/Pacific Islander/Other. Based upon survey responses, 29.1% had a high school education or less, 42.8% were married, 44.2% were employed, and 29.9% reported an annual household income <$15,000. Median body mass index (BMI) was 26.63 kg/m2 (IQR: 23.02, 30.90). In terms of lifestyle factors, 32.8% of patients were ever smokers, 56.8% self-reported regular alcohol use, 60% followed a restricted diet of some variety (e.g., low fat, low carbohydrate, vegetarian, vegan), 46.7% did not exercise regularly, 65.4% endorsed taking vitamins regularly, and 31.8% reported taking herbal supplements. The median AL score was 3.0 (IQR: 2.0, 4.0) (approximating the mean score and binarized score distribution of a BC cohort based in the U.K. Biobank). Pulse, systolic blood pressure, and blood glucose were the most common biomarkers to contribute to high AL (elevated in 74.3%, 67.1%, and 65.3% of high AL patients, respectively). BC patients with high vs. low AL were older, more likely to self-identify as NHB or Hispanic, have lower education and income, report other chronic illnesses, have a higher BMI, report less regular alcohol use, have lower physical activity levels, and lower vitamin/supplement use. In multivariable analysis, factors associated with high AL included older age (OR=1.01, 95% CI=1.00-1.01), NHB vs. NHW race (OR=1.14, 95% CI=1.04-1.24), and being unemployed vs. employed (OR=1.12, 95% CI=1.02-1.22). Diagnosis of stage III or IV BC compared to stage I disease was also significantly associated with high AL (OR=1.23, 95% CI=1.02-1.50 and OR=1.20, 95% CI=1.02-1.41, respectively). Discussion: In our diverse study population of BC patients, we found a significant correlation between sociodemographic and clinical factors and a biomarker of physiological stress, which has been associated with BC mortality. AL may be a useful biomarker to assess the effects of modifiable lifestyle factors and social determinants of health to improve BC clinical outcomes and reduce health disparities. Citation Format: Anna Vaynrub. Identifying Risk Factors for High Allostatic Load in a Racially/Ethnically Diverse Cohort of Breast Cancer Patients [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2024; 2024 Dec 10-13; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2025;31(12 Suppl):Abstract nr PS10-04.