Background: Coronary microvascular disease (CMD) is associated with increased cardiovascular (CV) risk in rheumatoid arthritis (RA). Studies suggest that higher RA disease activity is associated with a higher degree of CMD, as measured by coronary flow reserve (CFR). The objective of this study was to determine the association between reducing inflammation with changes in CV risk.

Methods: RA patients with active RA about to initiate a TNFi were enrolled (NCT02714881). All subjects underwent a cardiac perfusion PET scan to quantify CFR at baseline and after 24 weeks. A lower CFR in the absence of obstructive CAD is indicative of CMD, CFR< 2.5 defined CMD. Inflammatory markers and hs-cTnT were performed at baseline and 24 weeks. Primary and secondary outcomes was change in CFR and hs-cTnT, respectively, and tested by Spearman correlations.

Results: A total of 66 subjects completed the study, 80% female, mean RA duration 7.7 yrs. Estimated ASCVD risk was 5.6%, yet 47% had evidence of CMD.  We observed a significant reduction in all inflammatory markers between baseline and follow-up, along with improvements in RA disease activity; however, no change in the mean CFR or hs-cTnT was observed.   A reduction in hsCRP and IL-1beta was associated with a reduction in hs-cTnT. 

Conclusion: There was a high prevalence of CMD at baseline, but CFR did not significantly improve. Reducing inflammation was correlated with improvements in measures of CV risk, mainly in the subset of patients with detectable hs-cTnT, particularly via the IL-1beta pathway. These data suggest that hs-cTnT may be a useful marker when considering targeting inflammation to reduce CV risk in RA.