medwireNews: Plasma exchange (PLEX) is associated with a reduced risk for end-stage renal disease (ESRD) but an increased risk for serious infection in people with anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis, meta-analysis data show.
The updated analysis, published in The BMJ, also revealed that PLEX had no significant impact on all-cause mortality risk at 12 months in these patients.
The study, by Michael Walsh (St Joseph’s Hospital, Hamilton, Ontario, Canada) and co-investigators, included nine randomized controlled trials, of which one had not been included in a previous meta-analysis and two had been updated since the previous analysis.
The mortality findings, based on data from six trials involving 967 patients, showed no evidence of PLEX having a significant impact on all-cause mortality, whether overall or subgrouped by baseline kidney function or the presence or absence of lung hemorrhage.
ESRD outcomes at 12 months were reported in seven trials among 999 participants. Meta-analysis of these studies revealed, with moderate certainty, that PLEX was associated with a significant 38% reduction in the risk for ESRD, regardless of baseline kidney function.
Using the GRADE approach, the researchers determined that there was “moderate certainty” of an important effect in this case and note that it “is uncommon to generate this degree of certainty for such an impactful outcome in a rare disease.”
Walsh and team estimated that the absolute reduction in ESRD risk with PLEX was 0.08% for those at the lowest risk for ESRD (high certainty), 2.1% for those at low-moderate risk (low certainty), 4.6% for those at moderate-high risk (moderate certainty), and 16.0% for those at high risk (high certainty).
They point out that these findings are in contrast to those of the PEXIVAS trial, which found no reduced risk for ESRD with PLEX, but advise that the PEXIVAS trial was designed to measure the composite outcome of ESRD and all-cause mortality, not ESRD alone.
The investigators also found that PLEX increased the risk for serious infection at 12 months by 27% in data from four trials including 908 participants. They describe this as “a previously unrecognised effect” and say it “is an important finding as it may explain the lack of effect of PLEX on mortality despite the large effect on [ESRD].”
The absolute increase in serious infection risk with PLEX ranged from 2.7% for individuals at the lowest risk for infection (moderate certainty) to 13.5% among those at high infection risk (moderate certainty).
Relapse rates, serious adverse event rates, and quality of life were not affected by PLEX, and the data suggest that its impact on both ESRD and serious infections falls over time.
Walsh et al conclude: “This systematic review provides information regarding the benefits and harms of PLEX in [ANCA-associated vasculitis] necessary for decision makers.”
medwireNews is an independent medical news service provided by Springer Healthcare Ltd. © 2022 Springer Healthcare Ltd, part of the Springer Nature Group