OBJECTIVE:

To determine the frequency of aneurysm and dissection of the aorta in patients with giant cell arteritis and to assess the effects of these events on these patients.

DESIGN:

Population-based cohort study.

SETTING:

A multispecialty and a primary care clinic in southern Minnesota.

PATIENTS:

96 residents of Olmsted County, Minnesota, who developed giant cell arteritis between 1950 and 1985. The presence of aortic aneurysm, dissection, or both was confirmed using computed tomography, ultrasonography, angiography, or autopsy.

RESULTS:

11 of the 96 patients were found to have thoracic aortic aneurysms. In 2 of these patients, the aneurysms were detected when giant cell arteritis was diagnosed. In the remaining 9 patients, the aneurysms occurred a median of 5.8 years after giant cell arteritis was diagnosed. Six of the 11 died suddenly of acute thoracic aortic dissection. Five patients who did not have thoracic aortic aneurysms developed isolated abdominal aortic aneurysms a median of 2.5 years after giant cell arteritis was diagnosed. The incidence of thoracic aortic aneurysm in patients with giant cell arteritis was 999 per 100,000 person-years; the incidence of abdominal aortic aneurysm in these patients was 555 per 100,000 person-years. Compared with all persons of the same age and sex living in Olmsted County, patients with giant cell arteritis were 17.3 times (95% Cl, 7.9 to 33.0) more likely to develop thoracic aortic aneurysm and 2.4 times (Cl, 0.8 to 5.5) more likely to develop isolated abdominal aortic aneurysm.

CONCLUSIONS:

Giant cell arteritis is associated with a markedly increased risk for the development of aortic aneurysm, which is often a late complication and may cause death.