In patients with rheumatoid arthritis (RA), subclinical myocardial inflammation is frequent, associated with RA disease activity, and may decrease with RA therapy, according to results published in Arthritis & Rheumatology.
The study included participants with RA without known cardiovascular disease. Participants underwent cardiac 18-fluorodeoxyglucose positron emission tomography with computed tomography (FDG PET-CT). The researchers assessed myocardial FDG uptake visually and quantitatively assessed it with standardized uptake values (SUVs). They used multivariable linear regression to assess the associations between patient characteristics and myocardial SUV.
The researchers performed a second FDG PET-CT scan after 6 months on a subset of participants with RA who increased disease-modifying antirheumatic drug (DMARD) therapy (n=8) so that the investigators could assess treatment-associated changes in myocardial FDG uptake.
Of 119 participants, the researchers observed visually assessed FDG uptake in 37% (n=46), and 18% (n=21) had abnormal quantitatively assessed myocardial FDG uptake. Participants with a clinical disease activity index ≥10 had a 31% higher average SUV mean compared with participants with lower scores (P =.005) after adjusting for potential confounders.
Participants treated with non-tumor necrosis factor-targeted biologics had a 26% lower average adjusted SUV mean compared with those treated with conventional (nonbiologic) DMARDs (P =.029).
In the substudy, the researchers found that myocardial SUV mean decreased from 4.50 to 2.30 units over 6 months.
“The current study supports the hypotheses that myocardial inflammation in RA is related to disease activity, that it may contribute to the increased risk for heart failure in patients with RA compared with controls, and that it may be responsive to step-up therapy,” the researchers wrote.
Amigues I, Tugcu A, Russo C, et al. Myocardial inflammation, measured using 18-fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) is associated with disease activity in rheumatoid arthritis [published online November 8, 2018]. Arthritis Rheumatol. doi:10.1002/art.40771.