Abstract B29: Case-control study of metabolic syndrome and breast cancer in Puerto Rico
Authors: Ortiz Ana Patricia , Perez Cynthia , Mora Edna , Santiago Damarys , Sánchez Carola T. , Muñoz Cristina , Soto Marievelisse , Lee Mong-Hong 
Published: May 2015

Background: Breast cancer is the leading cancer type among women in the United States (US) and Puerto Rico (PR); incidence rates of breast cancer have increased in both of these populations in the last decades. In fact, Puerto Rico has highest prevalence of diabetes among all US states and territories. Diabetes, obesity and the metabolic syndrome (MS) are rapidly increasing in Hispanic populations, and research on the impact of these conditions on breast cancer among Hispanics is scarce.

Objectives: This study assessed the association of MS with breast cancer among Hispanic women in PR. The secondary aim was to assess the association of the individual components of the MS (hyperglycemia, dyslipidemia, abdominal obesity and elevated blood pressure) with breast cancer.

Methods: A matched clinic-based case-control study of 226 Hispanic women was performed between 2011 and 2013. One hundred thirteen cases and 113 controls were recruited in four clinics/hospitals in Puerto Rico and were individually matched by age (±5 years), menopausal status and recruitment site (response rate of 83% for cases and 84% of controls). Data collection procedures included a structured questionnaire, anthropometric and blood pressure measurements. According to the AHA/NHLBI definition, a woman was defined to have the MS if she had at least 3 of the following risk factors: waist circumference ≥35 inches, 2) triglycerides ≥150 mg/dL, 3) HDL &lt;50 mg/dL, 4) blood pressure ≥130/85 mm Hg and 5) fasting glucose ≥100 mg/dL. Conditional logistic regression models were used to describe the association of the MS and its individual components with breast cancer.

Results: Mean age of participants was 54.5 ±12.6 years. Prevalence of the MS was 53.2% among cases and 42.0% among controls. No significant differences were observed between cases and controls with regard to income, health care coverage, parity or smoking habits. Nonetheless, cases had significantly (p&lt;0.05) lower educational attainment than controls. After adjusting for educational attainment, the MS was marginally (p=0.09) associated with higher odds of breast cancer (OR=1.82, 95% CI=0.92-3.61). Elevated fasting glucose (OR=1.74, 95% CI=0.94-3.23, p=0.08) was also marginally associated to higher odds of breast cancer; however, high triglycerides (OR=1.22, 95% CI=0.67-2.20), elevated blood pressure (OR=1.68, 95% CI=0.88-3.18, p=0.11), elevated waist circumference (OR=1.55, 95% CI=0.86-2.81) and low HDL-C (OR=1.01, 95% CI=0.56-1.81) were not significantly associated with breast cancer.

Conclusions: This pilot study found marginal evidence of an association of the MS and elevated fasting glucose with breast cancer in a population of Hispanic origin. Future studies should assess this association using a larger sample size and considering the impact of tumor subtypes on breast cancer risk.

Grant Support: The project was supported by U54CA96297 and U54CA96300 from the UPR/MDACC Partnership for Excellence in Cancer Research, NCI & by the RCMI-Clinical Research Center grant G12RR03051 from the UPR Medical Sciences Campus.

Citation Format: Ana Patricia Ortiz, Cynthia Perez, Edna Mora, Damarys Santiago, Carola T. Sánchez, Cristina Muñoz, Marievelisse Soto, Mong-Hong Lee. Case-control study of metabolic syndrome and breast cancer in Puerto Rico. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr B29. doi:10.1158/1538-7755.DISP13-B29