Frequency and characteristics of severe relapses in giant cell arteritis.

Objectives: To assess the frequency and characteristics of severe relapse in patients with GCA in a real-life setting.

Methods: In a monocentric database of 530 patients, we retrospectively analysed patients who experienced at least one relapse and distinguished severe from non-severe relapses. Severe relapse was defined by the occurrence of an ischaemic event (ophthalmologic, neurologic, digestive, limb ischaemia), the occurrence of an aortic complication (i.e. new or worsening of aortic dilation, aortic dissection), or new or worsening vascular stenosis.

Results: From the cohort of 530 patients, 242 (45.7%) patients experienced relapse at least once, including 13 (2.5% of the cohort) who experienced severe relapse. Among the 464 recorded relapses, 14 (3% of all relapses) were severe. Severe relapse corresponded to the following vascular events: a peripheral limb ischaemia in six patients, a visual event in three patients (including two acute anterior ischaemic anterior neuropathies), an aortic complication in three patients, a mesenteric ischaemia in one patient and an ischaemic stroke in one patient. When compared with the 229 patients who experienced non-severe relapses, severe relapse patients were younger at diagnosis (P = 0.02), and showed more frequently limb claudication at baseline (P < 0.0001) and fewer GCA-related cranial signs (P < 0.0001). At diagnosis, more large-vessel vasculitis on imaging (82% vs 36%, P = 0.002) were observed in patients with severe relapse. The death rate did not differ between patients with severe and non-severe relapses.

Conclusion: In a real-life setting, relapse affects nearly half of GCA patients, but severe relapse is rare.