Abstract 2012: The Effect of Low-Dose Corticosteroids on Risk of Relapse in ANCA-Associated Vasculitis: A Systematic Review and Meta-Analysis of Clinical Trials
Phil Seo
Authors
M. Walsh, P. A. Merkel, A. D. Mahr, D. Jayne.
Background:
Many clinicians use low-dose glucocorticoids as an adjunctive therapy for the treatment of ANCA-associated vasculitis, even after the institution of steroid-sparing agents. Whether this is an effective treatment strategy, however, has been unclear. This study attempted to answer this question by performing a meta-analysis that used data from several randomized clinical trials of ANCA-associated vasculitis.
Methods:
This study included all prospective studies of Wegener’s granulomatosis or microscopic polyangiitis that were published after 1995 and used a standardized glucocorticoid taper. A random effects model was used to estimate the proportion of relapses; meta-regression, generalized linear multilevel modeling, and sensitivity analyses were used to determine sources of heterogeneity.
Results:
Eight hundred ninety-five patients from 7 randomized controlled trials and 3 uncontrolled trials were included in this analysis. Seven studies (representing 580 patients) attempted to taper patients completely off of glucocorticoids; 3 studies (representing 315 patients) continued to use low-dose glucocorticoids as part of remission maintenance therapy. Overall, 34% of patients suffered relapse over a mean of 22 months. The pooled proportion of relapse was significantly lower among patients enrolled in studies that allowed the use of low-dose glucocorticoids for maintenance therapy (13% versus 42%), but significant heterogeneity (P<0.001) was found.
Conclusions:
Studies of AAV have widely varying proportions of relapse which are, in part, explained by differences in CS tapering regimens. These data suggest that continued low-dose CS may be associated with fewer relapses. Furthermore, the potential impact of the use of low-dose CS should be considered in the design and sample size calculations for clinical trials in AAV.
Editorial Comment:
Many have observed that the relapse rate among patients enrolled in the placebo groups of clinical trials of ANCA-associated vasculitis has varied widely, implying that these patient groups are somehow different. One popular theory is that this variation is due to the use of low-dose glucocorticoids in some trials for remission maintenance. While this study implies that this theory is correct, the trials are too dissimilar (and the numbers of patients too small) to draw any solid conclusions. This study does, however, highlight the limitations of the current standard of care and the need to continue to search for better (and less toxic) therapies.
