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.