Introduction: Several cross-sectional and cohort studies have reported an association between serum markers of inflammation such as C-reactive protein, and coronary heart disease in Caucasian populations. We aimed to investigate the relationship between levels of serum C-reactive protein (hs-CRP) and the presence of coronary artery disease (CAD) in Iranian patients undergoing coronary angiography.
Methods: Serum hs-CRP, fasting lipid profile and blood glucose levels were measured in 110 patients (61 males and 49 females) undergoing routine coronary angiography. Anthropometric features including blood pressure were determined using standard procedures. Demographic characteristics, including post-menopausal status and smoking habit were assessed by questionnaire.
Results: Of the 110 subjects undergoing angiography, 74 (67.28%) had significant CAD (CAD+) and 36 (32.72%) were classified as having insignificant CAD (CAD-). Mean age (p<0.01), waist circumference (p<0.01) and LDL (p<0.05) and median values of hs-CRP (p<0.01) and triglycerides (p<0.05) were higher in the patients CAD+ than in the subjects CAD-. The proportion of women who were postmenopausal was also significantly higher in the CAD+ group. Age (p<0.01), waist circumference (p<0.05) and hs-CRP (p<0.05) were significant CAD predictive factors from logistic regression analysis. Serum hs-CRP concentrations were significantly higher in smokers compared to non-smokers (p<0.05), low density lipoprotein (LDL) (r=0.31, p<0.001), and serum triglycerides (r=0.191, p<0.05) correlated with serum hs-CRP. The median value of serum hs-CRP increased with the severity of the disease, but failed to reach statistical significance.
Conclusion: Serum hs-CRP is an independent predictor of angiographically defined CAD in an Iranian population. Measurement of the serum hs-CRP level may improve risk stratification among patients suspected of having CAD. The strong correlations between serum hs-CRP with LDL and smoking may be due to the putative pro-inflammatory effects of these two parameters. The association with serum triglycerides may be indirect and related to insulin resistance and adiposity.