Bone Density and Risk of Breast Cancer

摘要

The purpose of our study is to further evaluate the relationship between bone mineral density (BMD) and the risk of breast cancer among women age 65 years or older. All of the women are participants in the Study of Osteoporotic Fractures. We initially identified 121 cases of breast cancer over an approximate 3 years of follow-up. As part of the Department of Defense grant, we will extend the follow-up from 3 to 6 to 8 years. This extension will allow us to: (1) verify our findings of a 2.5 fold increase in risk of breast cancer among women with the highest BMD compared to women with the lower BMD; (2) improve our power to look at the association between exogenous estrogen use, BMD, vertebral fractures and breast cancer; and (3) improve our power to look at potentially important interactions including alcohol, estrogen, BMD and breast cancer and family history of breast cancer, BMD and breast cancer. The scope of work involves: (1) identifying potential breast cancer from the Year 6 (1992- 1994) and Year 8 (1995-1997) examination of the cohort; (2) obtaining medical records; (3) adjudication of cases; and (4) data analysis. The thrust of work during the first year of funding has been aimed at Number 1 through Number 3.