Objective: To evaluate the course of glucocorticoid (GC) therapy and associated adverse events in a population-based cohort of patients with giant cell arteritis (GCA).
Methods: We identified 125 Olmsted County residents with GCA diagnosed between 1950 and 1991 and obtained followup information on the 120 patients who were diagnosed antemortem and agreed to participate in this study. Clinical variables, GC doses, and GC adverse events on each patient were recorded. The relationship between GC therapy and the development of adverse events was studied by the Cox and Anderson-Gill proportional hazards models.
Results: All patients were treated with GCs and responded rapidly (median initial dosage 60 mg prednisone/day). The dosage was later reduced according to the treating physicians' judgment. The median duration required to reach 7.5 mg/day was 6.5 months and the median duration required to reach 5 mg/day was 7.5 months. Relapses or recurrences occurred in 57 patients. For the 87 patients followed to discontinuation of GC therapy and permanent remission of GCA (median of 22 months), the total median dose of prednisone was 6.47 gm. Adverse events associated with GCs were recorded in 103 (86%) patients and 2 or more events occurred in 70 patients (58%). Age and higher cumulative dose of GCs were associated with the development of adverse GC side effects.
Conclusion: GCs are therapeutically effective in GCA and the prednisone dosage was reduced to physiologic levels in three-fourths of the patients within 1 year. However, most patients developed serious adverse side effects related to GCs, indicating that less toxic therapeutic measures are needed.