Factors associated with radiographic progression in patients with Takayasu's arteritis.

OBJECTIVES To identify the factors related to radiographic progression in patients with Takayasu's arteritis (TAK). METHODS A retrospective cohort study was conducted among patients with TAK who underwent computed tomography angiography (CTA) at least twice in a 2-5-year interval. Radiographic progression was defined as newly developed and/or aggravated (more than 20%) characteristic CTA findings. Correlation analysis was performed using a multivariate Cox regression model. RESULTS The cohort included 153 TAK patients with a mean CTA interval of 3.53 years, and 24 (15.7%) showed radiographic progression. Those with progression showed higher acute-phase reactant levels (erythrocyte sedimentation rate [ESR], 26.06 vs. 35.72 mm/h, p=0.040; C-reactive protein [CRP], 0.45 vs. 1.13 mg/dL, p<0.001), were younger at the initial CTA (43.70 vs. 31.81 years, p<0.001), and were more likely to be receiving immunosuppressants (14 [10.9%] vs. 7 [29.2%] patients, p=0.038). Multivariate Cox regression analysis revealed age at the initial CTA (hazard ratio [HR]=0.945, confidence interval [CI]=0.898-0.995, p=0.030) and area under the curve (AUC) of CRP levels (HR=2.126, CI=1.046-4.319, p=0.037) as significant factors for radiographic progression. In a subgroup of patients with high CRP levels, 30.4% (14/24) showed progression; only age at the initial CTA was significantly different (37.03 vs. 27.10 years, p=0.012) between those with and without progression. CONCLUSIONS Higher CRP levels and younger age were risk factors of radiographic progression in patients with TAK. In the high CRP group, younger patients are more prone to progression and may need aggressive anti-inflammatory treatment.