Quantitative Computed Tomography Reveals the Effects of Race and Sex on Bone Size and Trabecular and Cortical Bone Density

Saeed, Isra; Carpenter, R. Dana; LeBlanc, Adrian D.; Li, Jing; Keyak, Joyce H.; Sibonga, Jean D.; Lang, Thomas F.

doi:10.1016/j.jocd.2009.04.001

« Previous Next »Journal of Clinical Densitometry
Volume 12, Issue 3 , Pages 330-336, July 2009

Quantitative Computed Tomography Reveals the Effects of Race and Sex on Bone Size and Trabecular and Cortical Bone Density

Isra Saeed
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
R. Dana Carpenter
- Address correspondence to: R. Dana Carpenter, PhD, Department of Radiology and Biomedical Imaging, University of California, San Francisco, 185 Berry Street, Suite 350, CA 94143-0946.
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
Adrian D. LeBlanc
- Division of Space Life Sciences, Universities Space Research Association, Houston, TX, USA
Jing Li
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
Joyce H. Keyak
- Department of Orthopaedic Surgery, University of California, Irvine, CA, USA
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, CA, USA
Jean D. Sibonga
- Division of Space Life Sciences, Universities Space Research Association, Houston, TX, USA
Thomas F. Lang
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA

Received 1 December 2008; received in revised form 27 March 2009; accepted 5 April 2009. published online 06 July 2009.

Abstract

To examine the effects of race and sex on bone density and geometry at specific sites within the proximal femur and lumbar spine, we used quantitative computed tomography to image 30 Caucasian American (CA) men, 25 African American (AA) men, 30 CA women, and 17 AA women aged 35–45yr. Volumetric integral bone mineral density (BMD), trabecular BMD (tBMD), and cross sectional area were measured in the femoral neck, trochanter, total femur, and L1/L2 vertebrae. Volumetric cortical BMD (cBMD) was also measured in the femur regions of interest. Differences were ascertained using a multivariate regression model. Overall, AA subjects had denser bones than CA subjects, but there were no racial differences in bone size. Men had larger femoral necks but not larger vertebrae than women. The AA men had higher tBMD and cBMD in the femur than CA men, whereas AA women had higher femoral tBMD but not higher femoral cBMD than CA women. These data support the idea that higher hip fracture rates in women compared with men are associated with smaller bone size. Lower fracture rates in AA elderly compared with CA elderly are consistent with higher peak bone density, particularly in the trabecular compartment, and potentially lower rates of age-related bone loss rather than larger bone size.