Abstract PO3-11-08: High Risk of Metabolic Dysfunction in Non-Obese Breast Cancer Survivors

Abstract Much literature already depicts the relationship between metabolic syndrome (MS), obesity, and breast cancer. Despite that, up to one-third of non-obese individuals may exhibit undiagnosed MS or metabolic dysfunction, posing an independent cancer risk and worse outcomes even for those with a body mass index (BMI) < 30kg/m². In that manner, our study aims to evaluate the metabolic profile of non-obese women with postmenopausal breast cancer compared to non-obese women without breast cancer. In this cross-sectional clinical study at the State University of São Paulo Medical School - UNESP. The study group (n=130) included women aged ≥ 45 and < 75 years, in amenorrhea for at least 12 months, BMI ≤ 30kg/m2, histological diagnosis of breast cancer, without metastatic disease, and without established cardiovascular disease (CVD). The control group (n=130) comprised women with all the same criteria except for breast cancer diagnosis. The groups were matched by age and menopause time in a ratio of one case to one control (1:1). We aimed to analyze their clinical, biochemical, and oncological data to establish relationships between these groups. We presented the data in tables 1 - 3. The groups showed homogeneity in age, time since menopause, BMI, waist circumference (WC), and cholesterol levels. There was a higher occurrence of MS and hypertension (HTN) among women treated for breast cancer compared to the control group (30.8% vs. 20.0% and 25.4% vs.14.6%, respectively) (p< 0.05). Similarly, a higher percentage of women treated for breast cancer had abnormal values for total cholesterol and glucose (56.2% vs. 43.1% and 29.2% vs. 15.4%, respectively) (p< 0.05). In the analysis of metabolic profile risk-adjusted for age time since menopause and BMI, women treated for breast cancer showed an increased risk for MS (OR=2.76, 95% CI 1.48-5.15), elevated glucose (OR=2.69, 95% CI 1.46-4.96), and HTN (OR=3.03, 95% CI 1.51-6.10). In the evaluation of factors influencing the metabolic profile, women with breast cancer had significantly higher mean values of WC (82.6±8.5 vs. 79.9±6.4 cm, p=0.048), systolic and diastolic blood pressure (129.2±17.1 and 77.7±8.8 mmHg vs. 118.2±15.1 and 73.6±8.8 mmHg, p=0.0002 and p=0.01, respectively), and glucose (99.7±32.5 vs. 86.6±7.6 mg/dL, p=0.0002) compared to control group. We conducted a sub-analysis among women with BMI < 25kg/m² from both groups. Women with breast cancer (n=64) had a higher occurrence of MS compared to women without breast cancer (n=53) (17.2% vs. 1.9%, respectively). Even though this sub-analysis did not reach the minimum number of patients with BMI < 25 kg/m² to achieve p value < 0,05, this analysis reveals a significant difference in MS incidence between the groups (p=0.007). This reinforces the hypothesis that oncological diagnosis substantially affects metabolic health, and therefore, breast cancer patients should receive special attention regarding their metabolic profile, regardless of their BMI. Conclusion: Non-obese women with breast cancer showed a higher risk of MS, HTN, and diabetes, with a worse metabolic profile than non-obese postmenopausal women without breast cancer. These findings suggest that postmenopausal women diagnosed with breast cancer, even in the absence of obesity, exhibit significant metabolic dysfunction characterized by a higher occurrence of MS and its components. The findings highlight the importance of a comprehensive assessment of metabolic health in women with breast cancer, regardless of their body mass index, to ensure appropriate and individualized care for these patients. Table 1 - Comparison of clinical and laboratory characteristics among 130 non-obese postmenopausal women with breast cancer and 130 non-obese postmenopausal women (control) (average values ± standard deviation). Table 2 - Comparison of categorized clinical and laboratory characteristics that influence the metabolic profile between 130 non-obese postmenopausal women with breast cancer and 130 non-obese postmenopausal women (control). Values expressed as number and percentage in parentheses. CA, cancer; WC, waist circumference; MS, metabolic syndrome; HDL, high-density lipoprotein, LDL, low-density lipoprotein; TG, triglycerides. *Significant difference p<0.05 (Chi-square Test). Table 3. Association between the presence of Metabolic Syndrome, and its clinical and laboratory components, among the 130 non-obese postmenopausal women with breast cancer and the 130 non-obese postmenopausal women (control). Values expressed as number and percentage in parentheses. CA, cancer; BP, blood pressure; WC, waist circumference; TG, triglycerides. *Odds ratio (OR) adjusted for age, menopause duration and BMI. **Significant difference if p<0.05 (Logistic Regression). Citation Format: Pedro Paulo Perroni Filho, Daniel Buttros, Eliana Aguiar Petri Nahas. High Risk of Metabolic Dysfunction in Non-Obese Breast Cancer Survivors [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-11-08.