Background Rheumatoid arthritis (RA) is associated with accelerated coronary atherogenesis1, myocardial infarction, and mortality. This risk transcends classic cardiac risk factors and may reflect the high inflammatory burden present in this condition.
Objectives We explored whether various plasma inflammatory biomarkers, or their combinations, predict coronary plaque presence and burden in patients with RA and no symptoms or prior diagnosis of coronary artery disease.
Methods One hundred and fifty RA patients underwent 64-slice computed tomography angiography (CTA); plaque was evaluated using a standardized AHA 15-segment model. Segment involvement score (SIS- n of segments with plaque), stenosis severity score (sum of individual segmental stenoses- SSS) and plaque burden score (sum of segmental plaque burden- PBS) were computed. High sensitivity cardiac Troponin-I (cTnI), tumor necrosis factor alpha (TNFα), vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), interleukin-17A and F (IL-17A, IL-17F), were quantified in plasma collected at the time of CTA, using the Erenna immunoassay System (Singulex, Alameda, CA). Linear regression models examined associations of individual biomarkers with all plaque outcomes. The ability of individual or combinations of binarized biomarkers to predict plaque outcomes was explored in logistic regression models adjusted for age and gender (model 1), or additionally for hypertension, diabetes, smoking, dyslipidemia, body mass index, and prednisone use (model 2).
Results Higher tertiles of cTnI correlated with plaque prevalence, as well as increasing CAC, SIS, SSS, and PBS (p-values 0.006, 0.005, 0.01, and 0.009 respectively – not shown). IL-6 and cTnI individually and independently predicted various plaque parameters after age and gender adjustments (model 1, table 1). The combination of elevated cTnI with elevated IL-6 predicted plaque burden after adjustments both for age and gender, as well as additional cardiac risk factors (model 2, table 1).
Conclusions In RA, biomarkers of cardiac dysfunction (cTnI) and inflammation (IL-6) can predict the presence and burden of coronary plaque as evaluated by CTA. Their associations and prognostic implications for atherosclerosis deserve further evaluation.
Karpouzas GA et al. Ann Rheum Dis. 2013 Jul 25. doi: 10.1136/annrheumdis-2013-203617.
Disclosure of Interest None declared