Background: The present study aimed to assess the relationship between vitamin D deficiency and the
severity of coronary artery disease (CAD) in a sample of Iranian diabetic patients.
Methods: This cross-sectional study was performed on 169 consecutive diabetic patients suspected of
CAD. The severity of CAD was defined based the number of involved coronary vessels. The
serum vitamin D level was measured via immunoassay, and its serum level was categorized as
normal (>30 ng/mL), insufficient (20–30 ng/mL), mildly-to-moderately deficient (10–20
ng/mL), and severely deficient (<10 ng/mL).
Results: There was no significant relationship between vitamin D deficiency and the number of
involved coronary vessels (P=0.423), and nor was there any difference in the serum level of
vitamin D in the individuals with CAD (24.84±18.53 ng/dL) and those without CAD
(22.37±16.88 ng/mL) (P=0.409). Our multivariate logistic regression model showed that
vitamin D deficiency could not predict the presence of CAD (OR=0.963, 95% CI: 0.666 to
1.392; P=0.842). Analysis of the area under the ROC curve indicated a low value for the
measurement of the vitamin D level in discriminating CAD from the normal coronary status
(AUC=0.533, 95% CI: 0.437 to 0.629; P=0.496).
Conclusions: Our study could not demonstrate a predictive role for vitamin D deficiency concerning
the severity of CAD in type 2 diabetes. Among the different CAD risk factors, smoking and
opium use were significantly correlated with vitamin D deficiency.