Relationship between Mammography Breast Density and Bone Mineral Density R. Gupta, 1,2 F. A. Alhajri, 2 A. M. Mohammed, * ,3 V. N. K. Chavan, 2 and P. Gupta 4 1 Department of Radiology, Faculty of Medicine, Kuwait University, Kuwait; 2 Department of Radiology, Mubarak Al-Kabeer Hospital, Kuwait; 3 Department of Nuclear Medicine, Faculty of Medicine, Kuwait University, Kuwait; and 4 Medical Student, Royal College of Surgeons, Dublin, Ireland Abstract 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 be- tween 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 (L1eL4) 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 corre- lation 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. Key Words: Bone mineral density; mammography breast density; menopausal status; obesity; osteoporosis. Introduction Mammography breast density (MBD) is a well-established strong indicator for breast cancer (1e3). Bone mineral den- sity (BMD), besides being a well-known indicator for osteo- porosis fractures (4), is also a predictor of breast cancer risk in women (5e9). Both MBD and BMD are linked to a com- mon pathway that involves estrogens (10,11) and are highly heritable. Genetic factors have been shown to explain about 60% of the age-adjusted MBD (12) and 50e80% of age- adjusted BMD (13). Furthermore, an association was observed between increased lifetime estrogen exposure and higher breast cancer risk (14), MBD (15,16), and BMD (17). The relationship between MBD and BMD is not clear and has not been studied well. To our knowledge, 2 studies (18,19) failed to show an association between MBD and BMD, whereas a third one (20) found a positive association, but only among hormonally untreated menopausal women. Also, there are significant ethnic differences in BMD, which persist after adjustment for bone size (21). We, therefore, evaluated the relationship between MBD and hip and spine BMD in an ethnically uniform group of Kuwaiti women. Methods Mammogram and BMD data of 248 women (aged 25e74 yr, mean age 52.29 Æ 6.94 yr) were studied, to look for any possible association between MBD and BMD. BMD was measured at total lumbar spine (L1eL4) and total left hip, using dual-energy X-ray absorptiometry scan on HOLOGIC densitometer. The women were divided into 3 Received 09/13/07; Revised 11/05/07; Accepted 11/05/07. *Address correspondence to: R. Gupta, MD, PhD, Department of Radiology, Faculty of Medicine, Kuwait University, P.O. Box 24923, 13110 Safat, Kuwait. E-mail: dr.renu@hotmail.com 431 Journal of Clinical Densitometry: Assessment of Skeletal Health, vol. 11, no. 3, 431e436, 2008 Ó Copyright 2008 by The International Society for Clinical Densitometry 1094-6950/08/11:431e436/$34.00 DOI: 10.1016/j.jocd.2007.11.001