Risk factors of breast cancer in Asian women： a Meta-analysis

Objective To evaluate the risk factors of breast cancer in Asian women and to provide evidences for establishing a risk assessment model. Methods Published studies concerning risk factors of breast cancer in Asian women were searched systemically and assessed by NOS （Newcastle-Ottawa Scale） items between 1995 and 2010. RevMan 4.2 software was used for data analysis and for calculating OR and its 95%CI on every risk factor. Results 27 studies including 403170 women were selected for Meta-analysis. According to NOS items, 20 studies were classified as A degree and 7 studies were evaluated as B degree. The risk factors of breast cancer and its pooled odds ratio values with statistical significance were as follows： 3.00 （95%CI： 1.68-5.36） when number of abortions≥3; 2.39 （95%CI： 1.78-3.21 ） when with family history of breast cancer; 1.54（95%CI： 1.30-1.82） when age at first live birth ≥30 （year）; smoking was 1.50（95%CI： 1.03-2.20）; 1.48（95%CI：1.20-1.83） with no live births; 1.29 （95%CI： 1.12-1.47） with no breast feeding; 1.26 （1.07-1.49）with age at menarche ≤12 （year） and 1.16（95%CI： 1.01-1.32） with alcohol drinking. Conclusion Number of abortions≥3, family history of breast cancer, age at first live birth ≥30 （year） ,smoking, no live births, no breast feeding, age at menarche ≤ 12 （year）, and alcohol drinking were among the priorities in the establishment of breast cancer risk assessment model for Asian women. Key words: Breast neoplasm;  Risk factors;  Meta-analysis;  Breast cancer risk assessment model