Supplementary Material for: Predictive Factors for the Long-Term Deterioration of Pulmonary Function in Interstitial Lung Disease Associated with Anti-Aminoacyl-tRNA Synthetase Antibodies

<b><i>Background:</i></b> Little has been reported on long-term pulmonary function trends among patients with interstitial lung disease associated with anti-aminoacyl-tRNA synthetase antibodies (ARS-ILD). <b><i>Objectives:</i></b> To clarify the factors predictive of progression in ARS-ILD based on patients’ initial clinical and radiological features. <b><i>Methods:</i></b> The clinical courses of 88 patients with &gt; 1 year of follow-up data on pulmonary function tests (PFTs) were retrospectively analyzed. Disease behavior was categorized into three groups: (1) improved or (2) worsened (defined as increases or decreases, respectively, of &gt; 10% in forced vital capacity and &gt; 15% in %diffusing capacity of lung carbon monoxide) or (3) stable based on PFT changes compared between 1-year results as the initial data and results at 3 years to assess the long-term course. <b><i>Results:</i></b> In the initial course of 75 patients with ARS-ILD who received anti-inflammatory therapy within 6 months after diagnosis, 48 patients (64.0%) improved and 6 patients (8.0%) worsened. The radiological patterns in the patients with ARS-ILD included nonspecific interstitial pneumonia (NSIP) in 46.7% and NSIP with organizing pneumonia overlap in 52.0% of the cases. One-third of the initially improved patients who worsened over the long-term course were assigned to the unstable group. By multivariate logistic analysis, middle lobe traction bronchiectasis was a significant predictive factor for the patients in the unstable group. <b><i>Conclusions:</i></b> Most patients with ARS-ILD receiving anti-inflammatory therapy had improved or remained stable in the first year. However, over the long-term course, some patients worsened despite their initial improvement. Even though the extent of the disease is limited, middle lobe traction bronchiectasis in ARS-ILD may be a useful predictor of poor long-term disease behavior.

背景：目前针对抗氨基酰-tRNA合成酶抗体相关性间质性肺疾病（anti-aminoacyl-tRNA synthetase antibodies associated interstitial lung disease, ARS-ILD）患者的长期肺功能变化趋势相关研究报道极少。研究目的：本研究旨在基于患者初始临床与影像学特征，明确ARS-ILD患者病情进展的预测因素。研究方法：本研究对88例具备≥1年肺功能检查（pulmonary function tests, PFTs）随访数据的患者临床病程进行了回顾性分析。以患者确诊后1年的肺功能检测结果作为基线数据，与3年随访时的检测结果对比，根据肺功能检查的变化情况将疾病转归划分为三类：（1）改善组：用力肺活量（forced vital capacity, FVC）升高≥10%且肺一氧化碳弥散量占预计值百分比（%diffusing capacity of lung carbon monoxide, %DLCO）升高≥15%；（2）恶化组：FVC降低≥10%且%DLCO降低≥15%；（3）稳定组：未达到上述改善或恶化判定标准，以此评估患者的长期病程。研究结果：在75例确诊后6个月内接受抗炎治疗的ARS-ILD患者中，初始病程内有48例（64.0%）病情改善，6例（8.0%）病情恶化。ARS-ILD患者的影像学表型包括：46.7%为非特异性间质性肺炎（nonspecific interstitial pneumonia, NSIP），52.0%为非特异性间质性肺炎合并机化肺炎（organizing pneumonia）重叠型。在初始病情改善但长期随访中出现恶化的患者中，有三分之一被归入不稳定组。经多因素logistic回归分析（multivariate logistic analysis），中叶牵引性支气管扩张是不稳定组患者的显著预测因子。研究结论：多数接受抗炎治疗的ARS-ILD患者在确诊后1年内病情可得到改善或维持稳定。但在长期随访过程中，部分初始病情改善的患者仍会出现病情恶化。即便病变范围有限，ARS-ILD患者出现的中叶牵引性支气管扩张仍可作为预测长期不良疾病转归的可靠指标。