Department of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Jiading Branch, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Front Immunol. 2024 Apr 30;15:1404828. doi: 10.3389/fimmu.2024.1404828. eCollection 2024.
Interstitial lung disease (ILD) is one of the common extramuscular involvement in idiopathic inflammatory myopathies (IIMs) (1). Several patients develop a progressive fibrosing ILD (PF-ILD) despite conventional treatment, resulting in a progressive deterioration in their quality of life (2). Here, we investigated the clinical and immune characteristics of IIM-ILD and risk factors for PF-ILD in IIM, mainly in anti-melanoma differentiation-associated protein 5 (anti-MDA5) dermatomyositis (DM) and anti-synthetase syndrome (ASS).
Here, a prospective cohort of 156 patients with IIM-ILD were included in the longitudinal analysis and divided into the PF-ILD (n=65) and non-PF-ILD (n=91) groups, and their baseline clinical characteristics were compared. Univariate and multivariate Cox analyses were performed to identify the variables significantly associated with pulmonary fibrosis progression in the total cohort, then anti-MDA5 DM and ASS groups separately.
Peripheral blood lymphocyte counts, including T, B, and NK cell counts, were significantly lower in the PF-ILD group than in the non-PF-ILD group. This characteristic is also present in the comparison between patients with anti-MDA5 DM and ASS. The multivariate Cox regression analysis revealed that age > 43.5 years [HR: 7.653 (95% CI: 2.005-29.204), p = 0.003], absolute NK cell count < 148 cells/μL [HR: 6.277 (95% CI: 1.572-25.067), p = 0.009] and absolute Th cell count < 533.2 cells/μL [HR: 4.703 (95% CI: 1.014-21.821), p = 0.048] were independent predictors of progressive fibrosing during 1-year follow-up for patients with anti-MDA5 DM, while absolute count of NK cells < 303.3 cells/µL [HR: 19.962 (95% CI: 3.108-128.223), p = 0.002], absolute count of lymphocytes < 1.545×10/L [HR: 9.684 (95% CI: 1.063-88.186), p = 0.044], and ferritin > 259.45 ng/mL [HR: 6 (95% CI: 1.116-32.256), p = 0.037] were independent predictors of PF-ILD for patients with ASS.
Patients with anti-MDA5 DM and ASS have independent risk factors for PF-ILD. Lymphocyte depletion (particularly NK cells) was significantly associated with PF-ILD within 1-year of follow-up for IIM-ILD.
间质性肺病（ILD）是特发性炎性肌病（IIM）常见的肌肉外表现之一（1）。尽管接受了常规治疗，仍有一些患者会发展为进行性纤维化ILD（PF-ILD），导致生活质量逐渐恶化（2）。在此，我们研究了特发性炎性肌病相关ILD（IIM-ILD）的临床和免疫特征，以及特发性炎性肌病中 PF-ILD 的危险因素，主要在抗黑色素瘤分化相关蛋白 5（抗-MDA5）皮肌炎（DM）和抗合成酶综合征（ASS）中进行了研究。
前瞻性纳入了 156 例 IIM-ILD 患者进行纵向分析，将其分为 PF-ILD（n=65）和非-PF-ILD（n=91）组，比较两组患者的基线临床特征。对总队列中与肺纤维化进展相关的变量进行单因素和多因素 Cox 分析，然后分别在抗-MDA5 DM 和 ASS 组中进行分析。
PF-ILD 组患者外周血淋巴细胞计数（包括 T、B 和 NK 细胞计数）显著低于非-PF-ILD 组。这一特征在抗-MDA5 DM 和 ASS 患者之间的比较中也存在。多因素 Cox 回归分析显示，年龄>43.5 岁[HR：7.653（95%CI：2.005-29.204），p=0.003]、绝对 NK 细胞计数<148 个/μL[HR：6.277（95%CI：1.572-25.067），p=0.009]和绝对 Th 细胞计数<533.2 个/μL[HR：4.703（95%CI：1.014-21.821），p=0.048]是抗-MDA5 DM 患者在 1 年随访期间发生进行性纤维化的独立预测因素，而绝对 NK 细胞计数<303.3 个/μL[HR：19.962（95%CI：3.108-128.223），p=0.002]、绝对淋巴细胞计数<1.545×10/L[HR：9.684（95%CI：1.063-88.186），p=0.044]和铁蛋白>259.45ng/mL[HR：6（95%CI：1.116-32.256），p=0.037]是 ASS 患者发生 PF-ILD 的独立预测因素。
抗-MDA5 DM 和 ASS 患者发生 PF-ILD 的风险因素不同。淋巴细胞耗竭（尤其是 NK 细胞）与 IIM-ILD 患者在 1 年内发生 PF-ILD 有显著相关性。
