Clinical Phenotypes of Giant Cell Arteritis: Insights into Complications and Survival Outcomes

Abstract

Background: Giant cell arteritis (GCA) is a heterogeneous disease with diverse clinical presentations and varying degrees of severity. This study aimed to assess the incidence of 3 clinical subsets in GCA and analyze associated severe complications and survival rates. By identifying distinct clinical patterns, the goal is to customize treatment approaches and minimize severe complications during follow-up.

Methods: This retrospective study classified clinical manifestations of GCA into 3 major phenotypes based on the reason for consultation: i) cranial, ii) extracranial, and iii) occult GCA. These groups were analyzed and compared for acute complications, including severe ischemic complications, "true" occlusive disease, and late complications such as aortic aneurysm. Survival data were also collected during follow-up.

Results: Visual disturbances were more common in the cranial GCA group compared to other subsets (P < .001). Blindness and stroke showed a clinically relevant trend, although statistical differences were not significant between the cranial GCA groups. Limb claudication was significantly more prevalent in the extracranial subset compared to the cranial or occult GCA subsets (12% vs. 2.6% vs. 0% respectively). Severe ischemic complications and true occlusive disease were more frequent in the cranial GCA groups (60%, P=.005 and 40%, P=1.64 respectively). Regarding mortality, there were no statistically significant differences in survival among the different clinical subsets. However, the occult GCA subset showed a trend towards a higher prevalence of deaths, both overall and specifically due to GCA.

Conclusion: Clinical subsets in GCA present distinct complications and survival outcomes, with the cranial subset showing a higher incidence of severe ischemic events and the occult subset associated with delayed diagnosis and increased mortality. Recognizing these subsets is crucial for tailored treatment approaches and improving patient prognosis. Further prospective studies are needed to refine diagnostic and therapeutic strategies.

Keywords: Clinical subsets; giant cell arteritis; mortality; severe ischemic complications; true occlusive disease.

Figure 1.

Temporal artery ultrasound in a patient with giant cell arteritis, cranial subset. Pathological characteristics by US in GCA: wall thickening (A), non-compressible arteries (B).

Figure 2.

¹⁸F-FDG-PET/TC in a patient with giant cell arteritis, extracranial subset. Vascular hypermetabolism compatible with vasculitis. (A) Whole body ¹⁸F-FDG PET/TC with ¹⁸F-FDG uptake, gray scale. High ¹⁸F-FDG uptake in the aorta and main arterial branches was detected, including subclavian, carotid, internal mammary, thoracic aorta, iliac, femoral, tibial arteries, and periarticular hypermetabolism in shoulders due to polymyalgia rheumatica, in relation to extracranial GCA subset. (B) Axial slices, spectrum color scale, with hypermetabolism in the thoracic aorta.

Figure 3.

Retinography of a patient with acute ischemic optic neuropathy and giant cell arteritis. Retinography with changes that reflect the impact of reduced blood flow to the optic nerve due to the inflammatory process associated. The optic disc (optic nerve head) appears swollen or edematous, with blurring of the optic disc margins.

Figure 4.

Computerized tomography with contrast, coronary view (A), axial view (B). Ascending aorta with circumferential thickening of the vascular wall and an aneurysm as a late complication of a patient with giant cell arteritis.