Relationship between mammography breast density and bone mineral density

Mammography breast density (MBD) is a well-established and strong predictive risk factor for breast cancer. Bone mineral density (BMD) is another predictor of breast cancer risk in women. Both MBD and BMD are linked to a common pathway, which involves estrogens, and are highly heritable. This study evaluated the relationship between MBD and hip and spine BMD in Kuwaiti women. Mammograms and BMD data of 248 women were studied. BMD was measured at total lumbar spine (L1-L4) and total left hip using dual-energy X-ray absorptiometry. The women were classified into 3 groups: normal, osteopenia, and osteoporosis by their BMD, using the World Health Organization criteria. They were divided into another 4 groups: fatty, fibroglandular, heterogeneously dense, and extremely dense breast according to their MBD and as defined by the Breast Imaging Reporting and Data System. All MBD and BMD data were analyzed statistically. Statistical analysis showed no significant difference or correlation between the MBD and BMD groups even after adjusting for obesity and menopausal status. However, a highly significant difference in body weight was found among the MBD groups (p<0.005). No correlation between MBD and BMD was observed in the group of Kuwaiti women who took part in the present study.