Background/Purpose: Traditional cardiac risk factors (CRFs) associate with myocardial infarction (MI) risk in both Rheumatoid arthritis (RA) and the general population. Subclinical atherogenesis has been linked to higher risk of future clinical events. However, the independent role of individual CRFs on coronary plaque presence and characteristics in asymptomatic, coronary artery disease (CAD)-naïve subjects with RA is unknown. We evaluated potential differences in the contribution of traditional CRFs on coronary plaque presence, quantitative and qualitative features in asymptomatic subjects with RA compared to controls.

Methods: One hundred and fifty RA subjects and 150 age and sex-matched controls underwent 64-slice coronary computed tomography angiography (CTA), a modality that reliably evaluates plaque presence, severity, burden, and composition as non-calcified (NCP), mixed or partially calcified (MP), or fully calcified (CP). A 15-segment American Heart Association model was used for evaluation. Quantitative plaque characteristics included segment involvement score (SIS- number of affected segments out of 15 evaluated/ patient), segment stenosis score (SSS-degree of luminal stenosis per segment, graded 1-4 and averaged over 15 evaluated segments/ patient), and plaque burden score (PBS- plaque extent per segment, graded 1-3 and averaged over 15 segments/ patient). Logistic and multivariable regression analysis models adjusted for age, gender, and all CRFs were used to assess differences in plaque prevalence and quantitative measures, between groups.

Results: Quantitative plaque measurements were significantly higher in RA; SIS=2.02±2.28 vs. 0.9±1.25, SSS=3.03±4.43 vs. 0.98±1.7, and PBS= 2.75±3.82 vs. 0.98±1.44, all with p<0.0001. Hypertension was significantly and differentially associated with higher risk of plaque prevalence in RA [adjusted OR=4.3 (1.83-10.1)- figure 1a]. Additionally, in the context of RA, the presence of male gender, hypertension and diabetes were associated with higher mean differences in the proportion of involved segments, plaque severity, and burden vs. their absence, compared to those imparted in controls (all with p<0.05- figure 1b, c, d respectively). Importantly, these differences segregated exclusively in MP and CP but not NCP.

Conclusion: Hypertension strongly and differentially associates with coronary plaque presence in CAD-naïve, asymptomatic subjects with RA compared to controls. In RA, male gender, hypertension and diabetes are associated with significant differences in plaque severity, burden and number of involved segments compared to presence of those factors in controls, specifically for MP and CP.