Risk Factors for Breast Cancer in Postmenopausal Women in Brazil

Purpose: To analyze risk factors for postmenopausal breast cancer. Methods: The present case-control study included 600 women treated at a cancer center reference hospital in a municipality in the South of Brazil. Results: Totals of 100 patients and 500 control subjects were evaluated. The mean age of the women was $52.5{\pm}11.9$ years; the average was $57.4{\pm}11.8$ years, and the average age of the control subjects was $51.5{\pm}11.7$ years. The risk factors for breast cancer that were considered included an age ${\geq}40$ years, postmenopausal status, a body mass index $(BMI){\geq}30kg/m^2$, and reduced physical activity. Variables like postmenopausal status and an obese BMI were associated with cases of breast cancer. Women who were postmenopausal or obese were 3.80 or 1.80 times more likely to develop breast cancer, respectively, and physically inactive women were 1.72 times more likely to develop breast cancer. Conclusions: Obesity and postmenopausal status are associated with the occurrence of breast cancer in this population. Being over 40 years of age was also a statistically significant factor for postmenopausal women.