A new predictor of disease activity in Takayasu’s arteritis patients: pericarotid fat density

To explore the incremental value of carotid pericarotid fat density (PFD) in the assessment of disease activity in Takayasu’s arteritis (TA). Sixty-one consecutive patients with TA from January 2010 to December 2021 were included in this study. Demographic and clinical characteristics, acute-phase reactants (APRs) and CTA indicator parameters were recorded. The effectiveness of CTA parameters including PFD in determining disease activity was assessed, with Erythrocyte Sedimentation Rate (ESR) used as a reference. A disease activity evaluation model was constructed to compare the benefits of the new model including PFD with ESR and Kerr scores by evaluating the consistency index (C-index), the net reclassification index (NRI) and the integrated discriminant index (IDI). In total, 29 (47.54%) cases showed active disease. The C-index of ESR to indicate disease activity was 0.778 (95% CI: 0.635, 0.874). The new activity assessment model combining ESR, maximal wall thickness and PFD showed significant improvement in C-index over the ESR method (0.902 vs. 0.778, P < 0.01; NRI 0.948, P < 0.01; and IDI 0.204, P < 0.01). In addition, the new model demonstrated a significant superiority over the Kerr score in terms of the C-index (0.902 vs. 0.771, P < 0.05), NRI (1.142, 95% CI: 0.730, 1.556, P < 0.01) and IDI (0.300, 95% CI: 0.187, 0.423, P < 0.01). In this cohort, CTA-derived perivascular fat density (PFD) showed association with disease activity in Takayasu’s arteritis patients and may provide complementary information to conventional assessment methods, suggesting its potential role in refining risk stratification. CTA-derived PFD provides incremental predictive value for disease activity in Takayasu’s arteritis patients, beyond conventional methods, improving risk stratification. PFD’s role in gauging TA disease activity evaluated. High PFD correlates with increased TA disease activity. PFD, wall thickness, and ESR surpass Kerr score in TA assessment.