2009 Southern Regional Meeting Abstracts

Purpose of Study: Coronary artery calcification is frequently associated with atherosclerotic disease. Abnormal levels of Ca²⁺ homeostasis mediators, such as vitamin D and PTH, have been implicated in the appearance of coronary artery calcification. We hypothesized that in patients with fluoroscopically proven coronary calcification, hypovitaminosis D could lead to secondary hyperparathyroidism facilitating calcification in the atherosclerotic coronary arteries.
Methods Used: We selected 27 patients, average age 64 (51-83) with coronary calcification apparent on fluoroscopy from patients referred for elective coronary angiography at our cath lab. Levels of 25 OH vitamin D, PTH, iCa, and phosphate were measured. Patients were excluded if they had serum creatinine >2.0, metabolic bone disease, primary hyperparathyroidism, gastric resection, inflammatory bowel disease, receiving insulin, glucocorticoids, growth hormone, thyroxine, altered Ca²⁺ homeostasis such as sepsis, pancreatitis, recent blood transfusion, recent surgery, excessive alcohol usage, metabolic alkalosis.
Summary of Results: 24 out of 27 patients (88%) with coronary calcification had serum 25 OH vitamin D <30 ng/mL, the lower limit of normal. PTH levels, however, were found to be normal (<65 pg/mL) in 22 out of 27 (81%) patients. Five patients had mild elevations of PTH levels. All of these five patients had low vitamin D levels. Levels of iCa, and PO₄ were within normal levels.
Conclusions: A high incidence of hypovitaminosis D was found in patients with fluoroscopically apparent coronary artery calcification. However, secondary hyperparathyroidism was not present in majority of patients as originally hypothesized. The exact role of hypovitaminosis D in calcification of atherosclerotic coronary arteries needs further investigation.