Incidence of aortic aneurysm, dissection, or rupture among patients with polymyalgia rheumatica and giant cell arteritis

Background

Patients with polymyalgia rheumatica (PMR) may have subclinical large vessel vasculitis. We compared the incidence of aortic complications in PMR and giant cell arteritis (GCA) to the general population.

Methods

A retrospective cohort study was performed of patients with PMR and GCA identified by ≥2 ICD-9/ICD-10-CM diagnostic codes and concurrent corticosteroid treatment in the US-based TriNetX database (2000–2024). Matched general population controls were identified (1:3 ratio). The primary outcome, aortic complications, was a composite of aortic aneurysm and dissection/rupture. Adjusted hazard ratios (aHR) were calculated using Cox proportional cause-specific hazard models with PMR as the referent category.

Findings

Of 57,336 patients, 17,327 had PMR, 4,734 had GCA, and 35,275 were matched controls. Median follow-up time was 3.74 years (interquartile range, 1.8–6.4). The incidence rate of any aortic complication per 1,000 person-years was highest for GCA (11.69), followed by PMR (6.78) and the general population (5.09). Compared to patients with PMR, patients with GCA had a higher risk of any aortic complication (aHR 1.87, 95 % confidence interval (CI) 1.58–2.21); the general population risk was similar (aHR 0.95, 95 % CI 0.84–1.06). In a sensitivity analysis, patients with PMR who later developed GCA had a risk similar to those initially diagnosed with GCA (aHR 0.85, 95 % CI 0.60–1.19).

Interpretation

Patients with PMR had a similar risk of large vessel complications compared to the general population and a lower risk compared to those with GCA. These results do not support screening for aortic inflammation among patients with PMR who lack features of GCA.