Aortic and Carotid Complications in Patients with Giant Cell Arteritis.

Purpose: To assess the risk of developing aortic aneurysms (AAs) and carotid artery stenosis (CAS) in patients with giant cell arteritis (GCA), particularly among those presenting with and without visual symptoms.

Design: Retrospective cohort study.

Subjects: A total of 7,294 patients aged ≥50 years with biopsy-proven GCA (temporal artery biopsy within two weeks of diagnosis and ≥3 prednisone refills) were identified and compared to 265,948 control patients presenting with tension-type headache utilizing the TriNetX US Collaborative Network. A secondary comparison was performed between GCA patients with (n=2,390) and without (n=5,222) visual symptoms (e.g., diplopia, amaurosis fugax, vision loss).

Methods: GCA was defined using ICD-10 codes M31.5 and M31.6. Patients with a history of other vasculitides, prior aortic aneurysms, or major thrombotic events were excluded. Propensity score matching (PSM) was used to balance demographics, socioeconomic factors, comorbidities, substance use, and laboratory/vital parameters, resulting in matched cohorts for each comparison. Adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models to account for time to onset of vascular complications.

Main outcome measures: Primary outcomes were the 5-year risks of (1) thoracic aortic aneurysms, (2) thoracoabdominal aortic aneurysms, (3) abdominal aortic aneurysms, and (4) carotid artery stenosis.

Results: After matching, 7,252 patients remained in each arm for the primary GCA versus control comparison. GCA patients had a significantly higher 5-year risk of any aortic aneurysm (3.59% vs 1.75%; aHR, 1.98; 95% CI, 1.59-2.45), including thoracic (2.23% vs 1.02%; aHR, 2.01; 95% CI, 1.59-2.77), thoracoabdominal (0.32% vs 0.14%; aHR, 3.68; 95% CI, 1.50-9.05), and abdominal (1.80% vs 0.82%; aHR, 2.03; 95% CI, 1.49-2.77). Carotid artery stenosis was also elevated in GCA (7.20% vs 4.37%; aHR, 1.59; 95% CI, 1.38-1.84). In the subanalysis of GCA patients, the 5-year risk of any aortic aneurysm was comparable between those with and without visual symptoms (3.58% vs 3.23%; aHR, 1.14; 95% CI, 0.83-1.57). However, carotid artery stenosis occurred more frequently in GCA patients presenting with visual symptoms (8.95% vs 7.43%; aHR, 1.24; 95% CI, 1.01-1.53).

Conclusions: Patients with GCA demonstrate a substantially increased risk of aortic aneurysms, particularly thoracic aortic aneurysms, compared to matched controls. Although having visual symptoms did not correlate with additional aortic risk, it was associated with a higher risk of carotid artery stenosis.