Pericoronary adipose tissue as a biomarker of coronary atherosclerosis and cardiovascular risk in rheumatoid arthritis

OBJECTIVES: Pericoronary adipose tissue attenuation (PCATa) on computed tomography angiography reflects coronary artery inflammation and associated with cardiovascular risk beyond atherosclerosis in general patients. We aimed to evaluate the relationships between PCATa and coronary atherosclerosis burden, progression and cardiovascular risk in rheumatoid arthritis (RA). METHODS: A total of 150 patients in a single-centre observational cohort underwent screening and surveillance coronary imaging 6.9 ±0.3 years later. PCATa around left anterior descending (LAD), left circumflex (LCx) and right coronary artery (RCA) were measured. Numbers of atherosclerotic segments (disease extent), plaque composition (noncalcified, low-density, mixed or calcified) and absolute volumes (mm3, plaque burden) were computed. RESULTS: Mean (adjusted incidence rate ratio 1.21 [95% confidence interval 1.02-1.27]), LCx (1.20 [1.00-1.43]) and RCA-PCATa (1.22 [1.02-1.46] per standard deviation (SD) increase) associated with total plaque numbers and variably with plaque subtype extent and burden at baseline. Mean and artery-specific PCATa exhibited diverse associations with total, noncalcified, low-density and calcified plaque progression. Using artery-specific PCATa thresholds, mean (adjusted hazards ratio 0.10 [95% CI 0.02-0.56]), LCx (0.11 [95% CI 0.03-0.43]) and RCA-PCATa (0.15 [0.04-0.53] per SD increase) were linked to cardiovascular risk. RCA-PCATa threshold in particular increased risk estimate accuracy (ΔAUC = 0.066 [bias-corrected 95% CI 0.024-0.126], P = 0.005). CONCLUSION: Mean and artery-specific PCATa associated with the extent, burden and composition of coronary plaque and its progression in RA. Mean, LCx and RCA-PCATa were linked to cardiovascular events, and RCA-PCATa specifically optimized risk estimates beyond atherosclerosis, highlighting its potential utility as a predictive biomarker.