Cross-sectional association of bone mineral density with coronary artery calcification in multi-ethnic middle-aged men ERA JUMP study

Background: Osteoporosis and coronary artery disease (CAD) are common diseases. Low bone mineral density (BMD) leads to osteoporosis and fractures. CAD is the leading cause of death in the US and the world. Coronary artery calcification (CAC) is a significant and independent predictor of future cardiovascular events. Some studies have revealed the inverse association between BMD and CAD in women. However, the evidence of the relationship is controversial in men, and little evidence exists in multi-ethnic middle-aged men. We hypothesized that there is a significant inverse association of BMD with CAC in middle-aged men. Methods: ERA JUMP study was a population-based study of 1,134 men aged 40 to 49 (267 Caucasians, 84 African Americans, 242 Japanese Americans, 308 Japanese, and 233 Koreans). The participants were examined for CAC, cardiovascular risk and other factors. CAC and the mean Hounsfield Unit value of vertebral bone (a surrogate for bone density) were studied using electron-beam computed tomography. CACs were quantified with the Agatston method. Vertebral bone density (VBD) was quantified by computing the mean HU value in manually outlined region of the T12 to L3 vertebrae. Robust linear regression and multiple logistic regression analyses were performed. Results: The mean VBD was 175.4 HU (standard deviation: 36.3 HU), the median of the CAC score was 0 (Interquartile range: (0, 4.5)), and the prevalence of CAC was 19.0%. VBD was significantly associated with CAC using robust linear regression (β=-0.2069, p-value=0.005). After adjusting for traditional cardiovascular risk factors, the relationship remained statistically significant (β=-0.1849, p-value=0.011). In logistic regression, the odds ratio (OR) of the presence of CAC for a one-unit increase in VBD was 0.9926 (95% CI: 0.9884-0.9969, p-value=0.001). The association persisted after adjusting for the same set of covariates (OR: 0.9950 95% CI: 0.9902-0.9999, p-value=0.045). Conclusions: There was a significant inverse association of our VBD surrogate with CAC in multi-ethnic middle-aged men. This study’s public health importance lies in the probability of the presence of common pathologies between BMD and CAC in multi-ethnic middle-aged men, which may lead to the development of new screening methods and treatments for osteoporosis and CAD in middle-aged men.