The Prevalence of Vitamin D Deficiency in Patients with Coronary Artery Disease and its Correlation with High Sensitivity C-Reactive Protein; A Report from Southern Iran

Background: Coronary Artery Disease (CAD) is the leading non-infectious cause of mortality in Iran. Inflammation plays an important role in CAD. Additionally, vitamin D deficiency is linked to a higher risk of cardiovascular mortality. Objectives: This study aimed to evaluate the prevalence of hypovitaminosis D in patients with CAD and to determine the level of high-sensitivity C-Reactive Protein (hs-CRP) as the main inflammatory marker. Methods: In this cross-sectional study, the prevalence of hypovitaminosis D was assessed in patients with CAD during 14 months. The study was approved by the Ethics Committee of Shiraz University of Medical Sciences. The patients were evaluated regarding the level of 25-OH cholecalciferol via high-performance liquid chromatography and hs-CRP level via enzyme linked immunosorbent assay. The related demographics, medical history, and lipid profile were evaluated, as well. Insufficient and deficient levels of 25-OH vitamin D were defined as < 30 ng/mL and < 12 ng/mL, respectively. The patients with insufficient vitamin D levels were evaluated regarding the hs-CRP level, as the cardiac inflammatory marker. The correlation between vitamin D level and hs-CRP was also determined using a bivariate method reporting Pearson's correlation coefficient in the SPSS software (IBM Corp., version 25). Results: In this study, hypovitaminosis D was reported in 257 (65.1%) out of the 395 patients with CAD. The mean age of the patients was 62.54 +/- 8.81 years, and 77 ones (55.0%) were female. Vitamin D deficiency was more prevalent in the patients with hs-CRP levels > 3 mg/L (P = 0.003). In addition, a significant negative correlation was observed between vitamin D serum level and hs-CRP (R = -0.601, P < 0.001). Conclusions: Vitamin D deficiency was prevalent in the patients with CAD, and decreased vitamin D levels were associated with increased hs-CRP levels. Hence, CAD patients should be evaluated regarding the vitamin D status.