Risk factors for breast cancer in women residing in urban and rural areas of eastern China.

Objective: To investigate breast cancer risk factors in Chinese women residing in urban and rural areas of eastern China using a large-scale cross-sectional survey.

Methods: In this multistage, stratified cluster sampling epidemiological survey, information on demographic characteristics, diet and lifestyle variables were gathered using a carefully designed questionnaire. Multivariate logistic regression analysis and subgroup analyses of the data were performed, including separate analyses of data from women residing in urban and rural areas.

Results: A total of 122,058 women were included in the survey. Age, body mass index, number of miscarriages, family history of breast cancer and menopausal status were found to be risk factors for breast cancer, while the consumption of soya bean products was a protective factor. Among women residing in urban areas, high or moderate intake of soya bean products and red meat were protective factors. Among women residing in rural areas, obesity and a high intake of milk were identified as risk factors for breast cancer, while a moderate intake of soya bean products was a protective factor.

Conclusions: This type of data is crucial for understanding the risk factors for breast cancer and could facilitate the development and targeting of effective intervention strategies, with the ultimate aim of breast cancer prevention.