Clinically overt aortic aneurysm in giant cell arteritis: a nationwide hospital-based study

To evaluate the incidence, time to aortic aneurysm (AA) diagnosis, and factors associated with AA development in patients admitted with giant cell arteritis (GCA).

We conducted a nationwide, registry-based study using the Spanish National Hospital Discharge Database. The study included all hospitalised patients aged ≥50 years with a diagnosis of GCA between 2016 and 2024.

Among 5,120 patients hospitalised because of GCA without prior AA, 54 (1.1%) were diagnosed with AA during current admission (AAo group) and 41 (0.8%) developed AA during follow-up (AAf group). Median time from first GCA admission and AA diagnosis was 2.7 years. Incidence rate was 1.8 per 100 patient-years. Established heart disease was markedly more frequent in the AAo compared with the other groups (50.0% at onset vs. 19.5% during follow-up and 32.3% in patients without aneurysm; p=0.006). After adjustment, male sex was independently associated with a higher risk of AA at baseline (RRR 2.42, 95% CI 1.40-4.20), whereas smoking at GCA diagnosis was the only factor independently associated with AA development during follow-up (RRR 3.23, 95% CI 1.47-7.08).

Clinically recognised AA was uncommon among hospitalised patients with GCA and was associated mainly with traditional cardiovascular risk factors, particularly male sex and smoking. Because estimates were based on hospital discharge diagnoses, they reflect clinically overt, hospital-recorded AA rather than the overall aneurysm burden in GCA. Follow-up should prioritise individualised vascular surveillance, particularly in smokers.