Both trabecular and cortical volumetric bone-mineral density (BMD) are associated with coronary-artery calcium score (CACS), but in different directions, according to a new pilot study. Trabecular volumetric BMD in the spine is inversely related to CACS, but the relationship between cortical volumetric BMD with CACS has not been reported before, researchers say. Dr. Claes Ohlsson of The Sahlgrenska Academy at University of Gothenburg, in Sweden, and colleagues compared the associations of trabecular and cortical volumetric BMD with CACS in their study of 541 women and 519 men aged 50 to 64 years. As previously shown, trabecular volumetric BMD was independently inversely associated with CACS. Cortical volumetric BMD, on the other hand, was independently directly associated with CACS greater than 0. A high ratio of cortical to trabecular volumetric BMD was significantly associated with an increased risk of CACS greater than 0 and with CACS greater than 100. All these associations between BMD and CACS were significant in women, but not in men, the researchers report in JAMA Cardiology. These findings "of opposite associations for trabecular and cortical volumetric BMD with CACS (suggest) a different role of trabecular and cortical volumetric BMD on the risk of coronary artery calcification, mainly in women. We propose that distinct pathophysiologic mechanisms exist for the trabecular versus cortical bone in the bone-vascular axis," the team writes. "Validation in independent cohorts should be performed to determine whether the cortical to trabecular volumetric BMD ratio, integrating information from both bone compartments, may be used as a risk marker for coronary artery disease in women," they note. Dr. Ohlsson did not respond to a request for comments. —Reuters Staff Source