Lifestyle, weight history, nutrition and breast cancer among non-gene carriers: a case-control study.

Abstract Abstract #6084 We conducted a nested case-control study of 280 French-Canadian women with breast cancer who were non-gene carriers (BRCA) and 280 women without cancer who were also non-gene carriers. A validated lifestyle questionnaire and a food frequency questionnaire were administered to obtain relevant information. It was found that age at the time the subjects reached maximum body mass index (BMI) was significantly associated with breast cancer risk [OR=2.83; 95% CI: (2.34-2.81)]. In addition, a significant association was noted between maximum weight gain at age 20 years [OR=1.68; 95% CI: (1.10-2.58)], 30 years [OR=1.96; 95% CI: (1.46-3.06)], and 40 years [OR=2.50; 95% CI: (1.72-3.97)] and breast cancer risk. Women who smoked more than 9 pack-years of cigarettes had a higher risk of breast cancer [OR=1.59; 95% CI: (1.57-2.87)]. Subjects who engaged in moderate physical activity had a 52% decreased risk of breast cancer [OR=0.48; 95% CI: (0.31-0.74)], but this was not evident for vigorous physical activity. It was observed that total energy intake was significantly associated with breast cancer risk [OR=2.54; 95% CI: (1.67-3.84)]. Women who drank more than 8 cups of coffee per day had 40% more chance of developing breast cancer [OR=1.40 (95% CI: (1.09-2.24)]. Subjects who consumed more than 9 grams of alcohol (ethanol) per day had the highest risk of breast cancer [OR=1.55 (95% CI: (1.02-2.37)]. None of the other nutrients and dietary components was significantly associated with non-gene carrier breast cancer risk. This study suggests that BMI, maximum weight gain during the second, third and fourth decades, smoking, total energy intake, and high intake of both alcohol and coffee may increase the risk of breast cancer among non-gene carrier French-Canadian women, while moderate physical activities may reduce the risk. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6084.