One-year survival benefit of plasma exchange in idiopathic inflammatory myositis patients with progressive interstitial lung disease-a systemic review and meta-analysis

Abstract

Objectives: This study aimed to systematically evaluate the efficacy of plasma exchange (PLEX) in patients with idiopathic inflammatory myositis (IIM) complicated by interstitial lung disease (ILD). Method: We conducted a comprehensive literature search in Medline and EMBASE from their inception to August 2023, focusing on randomized controlled trials, cohort studies, and case-control studies involving IIM patients with ILD treated with PLEX compared to those treated with standard therapies. The primary outcome was the one-year survival rate. All the statistical analyses were performed using RevMan version 4.12.0. Results: Out of 438 retrieved studies, 16 were selected for full-text review. Six cohort studies involving 148 patients with anti-melanoma differentiation-associated gene 5 (MDA5)-positive dermatomyositis or antisynthetase syndrome-related dermatomyositis with rapidly progressive ILD refractory to standard treatments (including glucocorticoids, immunosuppressive agents, or intravenous immunoglobulin) met the inclusion criteria. Patients receiving PLEX in addition to other therapies demonstrated a greater one-year survival rate (relative risk [RR] 1.59, 95 % CI 0.96–2.65, I2 52 %) than did patients in the non-PLEX group. Significance was reached in a sensitivity analysis after excluding one outlier (RR 1.71, 95 % confidence intervals [CI] 1.30–2.25; I2 0 %). Additionally, there was a trend suggesting that PLEX improved lung function, radiographic outcomes, and key serum biomarkers, such as Krebs von den Lungen-6 and ferritin. Funnel plot asymmetry suggested publication bias due to the lack of reporting of negative trials. All studies had a low risk of bias. Conclusions: As an adjunctive therapy, PLEX improved one-year survival in IIM patients with rapidly progressive ILD who were unresponsive to standard treatments.