Abstract
Objective
The Plasma Exchange and Glucocorticoids in Severe Antineutrophil Cytoplasmic Antibody–Associated Vasculitis (PEXIVAS) trial evaluated plasma exchange (PLEX) and glucocorticoid dose in antineutrophil cytoplasmic antibody–associated vasculitis (AAV). This study reanalyzed the PEXIVAS trial using Bayesian methods to focus on patients with diffuse alveolar hemorrhage (DAH).
Methods
In the PEXIVAS trial, adults with AAV and kidney injury and/or DAH were randomized to receive PLEX or no PLEX and reduced- or standard-dose glucocorticoids. This study evaluated 1-year survival and severe infection among participants with DAH, no DAH, and severe DAH (oxygen saturation ≤ 85% on room air or mechanical ventilation) across multiple priors. The secondary outcome was severe infection (leading to hospitalization, intravenous antibiotics, or death). This study calculated mean hazard ratios (HRs) for survival and odds ratios (ORs) for infection, 95% credible intervals (CrIs), and probabilities of survival benefit (HR 1).
Results
Among 704 participants (191 with DAH and 61 with severe DAH), using noninformative priors, the probability of improved survival was 93% for participants with DAH receiving PLEX (HR 0.52; 95% CrI 0.21-1.26) and 67% for those without DAH (HR 0.86; 95% CrI 0.43-1.71). Participants receiving reduced-dose glucocorticoids had a 98% probability of improved survival without DAH (HR 0.46; 95% CrI 0.22-0.95) but a 12% probability with severe DAH (HR 2.02; 95% CrI 0.64-6.35). Plasma exchange increased the odds of severe infection (OR 1.25; 95% CrI 0.92-1.70; 92% probability of OR > 1), whereas reduced-dose glucocorticoids decreased the odds of infection (OR 0.85; 95% CrI 0.63-1.15; 85% probability of OR
Conclusion
Patients with AAV and DAH may benefit from PLEX. Reduced-dose glucocorticoids improve survival for individuals without DAH but may be harmful in patients with severe DAH.