Thoracic Aortic Aneurysm and Giant Cell Arteritis: Clarifying the Link

We aim to better define the association between thoracic aortic aneurysm (TAA) and giant cell arteritis (GCA), thereby enhancing cross-diagnosis, monitoring, and therapy.Literature review: We used a two-step search approach to the available literature on the relationship between TAA and GCA. First, databases including PubMed, Web of Science, and Embase were searched. Additionally, relevant studies were identified through secondary sources including references of initially selected articles.Retrospective cohort study: We identified patients at our institution who were diagnosed with both TAA and GCA from January 1980 through December 2024. Descriptive statistics were used to support the association between these two diseases described in the literature.The literature review disclosed an increased incidence and relative risk of TAA among patients with GCA. GCA patients experienced progressive aortic enlargement, which may be due to vascular inflammation and disruption of elastin and collagen fiber biology in the vessel wall, resulting in mechanical weakness. Progressive aortic enlargement, including the aortic annulus, often results in aortic insufficiency (AI); in surgery, complete aortic replacement is recommended. Predictors of aneurysmal disease included AI and severe inflammatory response at the time of GCA diagnosis, as well as risk factors such as male sex, hypertension, hyperlipidemia, coronary disease, diabetes, and smoking.The investigation at our institution revealed that among 2,344 patients with GCA, 72 developed TAA, an incidence of 3.1%. Among those, 61 (84.7%) had an ascending aortic aneurysm, 5 (6.9%) had a descending aortic aneurysm, and 6 (8.3%) had both. Of these, 33 (45.8%) were male, 66 (91.7%) had hypertension, 44 (61.1%) were former or current smokers, 16 (22.2%) had diabetes mellitus, 66 (91.7%) had hyperlipidemia, 31 (43.1%) had coronary disease, 33 (45.8%) had concomitant polymyalgia rheumatica, and 21 (29.2%) had AI at the time of GCA diagnosis.Our study highlights a 3.1% incidence of TAA in GCA patients, with hypertension, smoking, and hyperlipidemia as the most common additional risk factors. Ascending aortic aneurysms were the most frequent, occurring in 84.7% of TAA in GCA cases. These findings emphasize the importance of monitoring for TAA in the GCA population.