Relapse in giant cell arteritis occurs in 47.2% of patients treated with only glucocorticoids, a rate that is likely due to the short duration of glucocorticoid regimens rather than the size of the initial induction dose, according to data published in Arthritis Care & Research.
“Most studies consider that GCA does not significantly affect survival,” Sabine Mainbourg, MD, of Claude Bernard University in Lyon, France, and colleagues wrote. “The recommended treatment at diagnosis is high-dose glucocorticoid (GC) therapy (0.7-1 mg/kg/day of prednisone), followed by progressive tapering when the disease is controlled and until GC withdrawal. The duration of treatment is still debated, and a significant number of patients remains on long-term low-dose GCs in order to prevent relapse.”
To analyze the prevalence of GCA relapse among patients receiving glucocorticoids alone, Mainbourg and colleagues conducted a systematic literature review, using MedLine to search for articles published up to December 2017. The researchers included studies with patients with newly diagnosed or relapsed GCA, as well as participants treated with glucocorticoids alone — either as part of a control group or in trials evaluating glucocorticoid-sparing agents. Studies were excluded if the various groups were not well-defined, or if there was doubt regarding the type of treatment.
The relapse rate in patients with GCA treated with only glucocorticoids likely owes more to the short duration of glucocorticoid regimens than the size of the initial induction dose, according to Mainbourg.
Mainbourg and colleagues identified 259 potentially relevant studies, of which 131 were extracted from the meta-analysis addressing GCA. In total, 34 studies were included in the final analysis, representing eight randomized clinical trials, 35 arms of glucocorticoid treatment and 2,505 patients.
According to the researchers, the prevalence of relapse was 47.2% (95% CI, 40-54.3), with a high heterogeneity (I2 = 93%). Relapse was significantly more prevalent among patients randomized clinical trials, compared with those included in observational studies (P < .0001). However, prevalence was not significantly different according to design (P = .06). In addition, relapse rate was associated with year of publication (P < .0001) and shorter glucocorticoid regimens (P < .001), with the period of scheduled glucocorticoid treatment being shorter in randomized clinical trials compared with observational studies.
“GCA relapses occur in half of patients receiving GC alone, without improvement across decades,” Mainbourg and colleagues wrote. “Relapse rate is more related to short duration of GC administration than to initial dose at induction. The results challenge the GC regimen used in RCTs and thereby question the extent of the real effect of methotrexate and tocilizumab. These results support randomized controlled trials designed with control arms treated with GC for at least 12 months.” – by Jason Laday
Disclosure: The researchers report no relevant financial disclosures.