Management and outcomes of interstitial lung disease associated with anti-synthetase syndrome: a systematic literature review

Abstract

Background Anti-synthetase syndrome (ASS) is a chronic autoimmune condition, with interstitial lung disease (ILD) being a key feature. This systematic literature review (SLR; CRD42023416414) aimed to summarise treatments and outcomes of ILD associated with ASS (ASS-ILD). Methods Databases were searched for articles discussing ASS-ILD management and outcomes, published 1946-September 2023. Screening and data-extraction were performed by two reviewers. Meta-analysis, using a random effects model, and paired t-tests, were undertaken where appropriate to evaluate post-treatment-change in Pulmonary Function Tests (PFT). Results Ten articles were included, comprising 514 patients: 67.8% female, mean age 52.4years (SD4.6). Baseline high-resolution computed tomography was documented in 447 patients (86.9%); the most common pattern was non-specific interstitial pneumonia (n = 220; 49.2%). The most common myositis-associated autoantibody was anti-Jo1 (48%) with 27.8% having associated anti-Ro52 antibodies. Pooled estimates, after meta-analysis, for baseline Forced Vital Capacity (FVC) was 60.8% predicted (SE 2.1), and Diffusion Capacity of Lungs for Carbon Monoxide (DLco) was 49.8% (SE 3.5). After one-year, pooled improvement in FVC was 14.1% from baseline (SE 3.1) and in DLco was 15.1% (SE 2.8). Paired t-test demonstrated significant overall improvement in FVC (p = 0.007) and DLco (p = 0.002). Patients receiving RTX had 12.2% improvement in FVC and 2.9% increase in DLco at one-year; for patients receiving CYC, there was 17% improvement and 6.3% increase, respectively. 28 deaths were reported. Conclusion Our SLR, the first to summarise management and outcomes of ASS-ILD, found no conclusive difference between effectiveness of treatments. More robust trials are required to reduce morbidity and mortality resulting from ASS-ILD.