Low bone mineral density (BMD) is associated with obstructive coronary artery disease (CAD); this article reviews several recent studies that have demonstrated the association. In one study, for every 1-unit reduction in femoral neck T score, a 0.23 minute decrease in treadmill exercise duration was found after values were adjusted for age and other patient characteristics (95% confidence interval [CI], 0.11–0.35, p<0.001). For every 1-unit reduction in femoral neck T score, there was a 22% increased risk of myocardial ischemia after values were adjusted for age and other patient characteristics (95% CI, 1.06–1.41, p = 0.004). Overall after adjustments, patients with a low BMD who were referred for exercise echocardiographic stress testing had a 43% greater risk of myocardial ischemia than did patients with normal BMD referred for exercise echocardiographic stress testing (95% CI, 1.06–1.94, p = 0.02). Reduced physical activity may contribute to both low BMD and CAD through the development of atherosclerotic vascular disease.
In a second study, stress test-induced myocardial ischemia developed in 95 of 254 patients (37%) with osteoporosis, in 81 of 260 patients (31%) with osteopenia, and in 62 of 251 patients (25%) with normal BMD (p= 0.009) (p= 0.002 comparing osteoporosis with normal BMD; p=0.007 comparing osteoporosis or osteopenia with normal BMD). Patients with osteoporosis or osteopenia had a 1.7 times higher chance of stress test-induced myocardial ischemia than those with normal BMD after controlling the confounding effects of systemic hypertension, diabetes mellitus, body mass index, and age.
Key words: osteoporosis, osteopenia, bone mineral density, coronary artery disease, myocardial ischemia.