We aimed to describe the initial treatment that was used in a common hospital-based practice in patients with giant-cell arteritis with and without large-vessel involvement at diagnosis as well as the outcomes in both groups.

This retrospective multi-center cohort included patients with giant-cell arteritis diagnosed between 2005 and 2015, all of whom had fluorodeoxyglucose (FDG) positron emission tomography combined with computed tomography (FDG-PET/CT) performed at giant-cell arteritis diagnosis and were followed up for ≥12 months. We compared the features, treatment, and outcomes of patients with large-vessel involvement demonstrated on FDG-PET/CT with those of patients with a negative PET/CT.

Eighty patients (50 women, median age: 71 [53-87] years) were included, 40 of whom had large-vessel involvement demonstrated on FDG-PET/CT and 40 who did not. After a median 56-month follow-up time, 42 (53%) patients had discontinued glucocorticoid (GC) treatment. Patients with and without large-vessel involvement were indistinguishable in the initial median dose of prednisone (0.74 mg/kg vs 0.75 mg/kg, P = .56), overall GC duration (P = .77), GC discontinuation rate (P = .65), relapse rate (P = .50), frequency of GC-dependent disease requiring GC-sparing treatments (P = .62), and fatality rate (P = .06).

In the setting of tertiary hospital recruitment, large-vessel involvement at giant-cell arteritis diagnosis using a PET/CT study had no influence on the choice of initial GC dose and had no impact on outcomes. Prospective studies are required to confirm these findings.