Evaluation of vitamin D levels in relation to coronary CT angiographic findings in an Iranian population

BACKGROUND Vitamin D deficiency, as a predisposing factor for coronary artery disease (CAD), is a subject of increasing interest. However, its role as a risk factor has not been proven. This study aimed to investigate the relationship between serum vitamin D levels and CAD. MATERIALS AND METHODS Using a cross-sectional design, 180 patients who were candidates for coronary computed tomography angiography (CCTA) were selected. Serum levels of vitamin D were measured and compared with the results of CCTA (including calcium score, and presence and severity of coronary artery involvement due to atherosclerotic plaques). RESULTS The mean age of the participants was 60.5±10.6 years and the mean serum vitamin D level was 26.2±15.9 ng/dL (range, 3.5-83.2 ng/dL). Overall, 6.1% of the participants (n=11) had vitamin D deficiency, 56.1% (n=101) had insufficient levels of vitamin D, and 37.8% (n=68) had sufficient levels of vitamin D. The mean serum vitamin D level was significantly lower in patients with severe CAD (P=0.004). The serum vitamin D level in the "positive for CAD" group was 20.98 ng/mL, significantly lower than the level in the "negative for CAD" group (30.47 ng/mL; P<0.001). The mean calcium score among participants was 533.5±87.9. Based on the Spearman test, a significant negative correlation (-0.21) was detected between the serum vitamin D level and coronary artery calcium score (CACS) (P=0.005). Conversely, the mean CACS in the vitamin D deficient group was significantly higher than in the insufficient and sufficient vitamin D groups (P<0.001 for both comparisons). CONCLUSION Vitamin D deficiency was associated with coronary artery calcification and severity of coronary artery stenosis in Iranian patients.