Large-vessel giant cell arteritis: a cohort study

Objective. The aim of this study was to compare baseline variables, treatment and outcomes in patients with large-vessel GCA (LV-GCA), primarily of the upper extremities, with those with cranial disease (C-GCA). Methods. All patients >50 years of age with radiographic evidence of subclavian LV-GCA diagnosed between 1 January 1999 and 31 December 2008 were identified and compared with those with biopsypositive C-GCA diagnosed in the same period. Results. The study included 120 LV-GCA patients and 212 C-GCA patients. Compared with C-GCA, patients with LV-GCA were younger [68.2 years (S.D. 7.5) vs 75.7 (7.4), P<0.001] and had longer duration of symptoms at GCA diagnosis (median 3.5 vs 2.2 months, P<0.001). A history of PMR was more common in LV-GCA patients (26% vs 15%, P = 0.012), but a smaller proportion had cranial symptoms (41% vs 83%, P<0.001) and vision loss (4% vs 11%, P = 0.035). ACR classification criteria for GCA were satisfied in 39% of LV-GCA patients and 95% of C-GCA patients (P<0.001). Compared with C-GCA, patients with LV-GCA had more relapses (4.9 vs 3.0/10 person-years, P<0.001), higher cumulative corticosteroid (CS) doses at 1 year [11.4 g (S.D. 5.9) vs 9.1 (S.D. 3.7), P<0.001] and required longer treatment (median 4.5 vs 2.2 years, P<0.001). Conclusion. Although patients with LV-GCA had a lower rate of vision loss, they had a higher relapse rate and greater CS requirements. The ACR criteria for GCA are inadequate for the classification of patients with LV-GCA.