Patients with inflammatory rheumatic diseases (IRDs) have a higher morbidity and mortality from accelerated atherosclerosis than the general population. We hypothesized that patients with the combination of IRD and coronary artery disease (CAD) would have a certain inflammatory phenotype compared with CAD patients without this comorbidity.
Four groups of patients were included: patients with IRD, referred to coronary artery bypass grafting (CABG) (CAD-IRD, n = 67), patients without IRD, referred to CABG (CAD, n = 52), patients with IRD without CAD (IRD, n = 32) and healthy controls (n = 30). Plasma levels of several inflammatory markers were analysed by enzyme immunoassays.
(i) Plasma levels of markers of endothelial cell activation [i.e. vascular cell adhesion molecule-1 (VCAM-1) and von Willebrand factor] and osteoprotegerin (OPG) were significantly increased and plasma levels of CCL21 significantly decreased in CAD-IRD patients as compared with CAD patients without IRD. (ii) Within the CAD-IRD group, acute coronary syndrome was a significant predictor of OPG, suggesting an enhanced inflammatory response during plaque destabilization in CAD-IRD patients. (iii) Plasma levels of VCAM-1, OPG and CCL21, but not lipid parameters, IRD characteristics and several other inflammatory markers (e.g. CRP), were significant predictors of CAD-IRD as opposed to CAD in two logistic regression models.
Our findings further support a role for inflammation in the accelerated form of atherosclerosis in IRD patients, and suggest that certain inflammatory pathways, such as the enhanced endothelial cell activation and the RANK ligand/RANK/OPG system, may be of particular importance.