Analysis of the Relationship between Body Mass Index and Breast Cancer Incidence in Korean Women

ABSTRACT

PURPOSE: Obesity in women has been shown to have correlation with breast cancer incidence. The proportion of Korean women who are obese has increased recently. However, there is no large-scale study evaluating the relationship between obesity and breast cancer incidence in Korea. In this study, we tried to identify the relationship between obesity and breast cancer incidence in Korean women by using body mass index (BMI). METHODS: A retrospective analysis was performed using single-center data of 28,631 patients screened with breast ultrasonography or mammography between January 2009 to December 2013 in Seoul National University Hospital Healthcare System Gangnam Center. Their clinical characteristics were evaluated. The correlations between breast cancer incidence with BMI and other factors were analyzed using univariate and multivariate logistic regression models. RESULTS: A total of 28,631 patients were enrolled; 67 patients were diagnosed with breast cancer. Among patients without breast cancer, the proportion of patients with BMI under 23 was 68.1%, whereas it was 56.7% among patients with breast cancer (p=0.036). In univariate analysis, patients with a BMI over 25 had an odds ratio of 2.09 for breast cancer compared with those with a BMI under 23 (p=0.012). In addition, patients with a waist circumference over 85 cm had an odds ratio of 1.69 for breast cancer compared with the others (p=0.042). In multivariate analysis, BMI also had significant correlation with breast cancer incidence (odds ratio=1.87, p=0.035). CONCLUSION: An increase in BMI has positive correlation with breast cancer incidence in Korean women. However, a multi-centered prospective study is needed for further evaluation.