Serum osteocalcin is associated with dietary vitamin D, body weight and serum magnesium in postmenopausal women with and without significant coronary artery disease

Osteoporosis and atherosclerosis often present atypically in postmenopausal women, making clinical recognition difficult. Prospective studies suggest independent associations between bone mass and vascular calcification through vitamin D deficiency as an established predictor of both conditions. We aimed to examine the relationship between serum osteocalcin and vitamin D status in postmenopausal women with and without angiographic evidence of coronary artery disease (CAD). One hundred and eighty postmenopausal women undergoing coronary angiography were selected sequentially from the Catheterization unit of King Abdulaziz University Hospital. Socio-demographic, anthropometric parameters and dietary habits were measured. Biochemical variables were estimated in blood samples. Half of the postmenopausal women did not have significant CAD, 24% had significant CAD in a single and/or double coronary vessels, 26% had significant CAD in three coronary vessels. Mean serum vitamin D concentrations showed that vitamin D deficiency was a common finding in the whole population. Vitamin D and calcium intakes were uniformly low in the study cohort. Serum osteocalcin was significantly correlated with dietary vitamin D in all subgroups (r=-0.172, p<0.05) and positively correlated among the patients (r=0.269, p=0.01). Serum magnesium, alkaline phosphatase, dietary vitamin D, and body weight were independent variables of serum osteocalcin level. In conclusion, elevated levels of serum C reactive protein and vitamin D were associated with low serum osteocalcin levels. Therefore, osteocalcin may be a potential cardiovascular risk marker. However, further studies are needed to clarify the pathophysiological processes underlying the relationship between serum osteocalcin level and atherosclerosis parameters.