Department of Rheumatology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, National Clinical Research Center for Dermatologic and Immunologic Diseases (NCRC-DID), Key Laboratory of Rheumatology & Clinical Immunology, Ministry of Education, Beijing, China.
Eight-year Medical Doctor Program, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
Front Immunol. 2023 Aug 17;14:1211790. doi: 10.3389/fimmu.2023.1211790. eCollection 2023.
Interstitial lung disease (ILD) is a relatively prevalent extra-articular manifestation of rheumatoid arthritis (RA) and contributes to significant morbidity and mortality. This study aimed to analyze the association between chitinase-3 like-protein-1(CHI3L1) and the presence of RA-ILD.
A total of 239 RA patients fulfilling the American Rheumatism Association (ACR) 1987 revised criteria were enrolled and subclassified as RA-ILD and RA-nILD based on the results of high-resolution computed tomography scans (HRCT) of the chest. The disease activity of RA was assessed by Disease Activity Score for 28 joints (DAS28) and categorized as high, moderate, low, and remission. Chemiluminescence immunoassays were applied to determine the serum levels of CHI3L1. Univariate analysis was performed and the receiver operating characteristics (ROC) curves were plotted to evaluate the correlation between RA-ILD and CHI3L1.
Among the eligible RA patients studied, 60 (25.1%) patients were diagnosed with RA-ILD. Compared with RA-nILD, RA patients with ILD had significantly higher median age (median [IQR], 68.00 [62.00-71.75] vs 53.00 [40.00-63.00], p<0.001) and a higher proportion of males (21 (35.0%) vs 30 (16.8%), p=0.003). Notably, differences in DAS28 scores between the two groups were not observed. The serum level of CHI3L1 was significantly higher in RA-ILD patients (median [IQR], 69.69 [44.51-128.66] ng/ml vs 32.19 [21.63-56.99] ng/ml, p<0.001). Furthermore, the areas under the curve (AUC) of CHI3L1 attained 0.74 (95% confidence interval [CI], 0.68-0.81, p<0.001) in terms of identifying patients with RA-ILD from those without ILD. Similar trends were seen across the spectrum of disease activity based on DAS28-ESR.
Our findings of elevated serum CHI3L1 levels in RA-ILD patients suggest its possible role as a biomarker to detect RA-ILD noninvasively.
间质性肺病（ILD）是类风湿关节炎（RA）较为常见的关节外表现，可导致较高的发病率和死亡率。本研究旨在分析壳三糖酶蛋白-3 样蛋白-1（CHI3L1）与 RA-ILD 之间的关系。
共纳入 239 例符合美国风湿病学会（ACR）1987 年修订标准的 RA 患者，并根据胸部高分辨率计算机断层扫描（HRCT）结果将其分为 RA-ILD 和 RA-nILD。采用疾病活动评分 28 关节（DAS28）评估 RA 的疾病活动度，并分为高、中、低和缓解。采用化学发光免疫分析法测定血清 CHI3L1 水平。进行单因素分析，并绘制受试者工作特征（ROC）曲线评估 RA-ILD 与 CHI3L1 之间的相关性。
在符合条件的 RA 患者中，60 例（25.1%）患者被诊断为 RA-ILD。与 RA-nILD 相比，ILD 患者的中位年龄[中位数（IQR），68.00（62.00-71.75）岁比 53.00（40.00-63.00）岁]明显更高（p<0.001），男性比例更高[21 例（35.0%）比 30 例（16.8%）]（p=0.003）。两组间 DAS28 评分差异无统计学意义。RA-ILD 患者血清 CHI3L1 水平明显更高[中位数（IQR），69.69（44.51-128.66）ng/ml 比 32.19（21.63-56.99）ng/ml]（p<0.001）。此外，CHI3L1 的曲线下面积（AUC）在 0.74（95%置信区间[CI]，0.68-0.81，p<0.001），可用于从无 ILD 的患者中识别出 RA-ILD 患者。基于 DAS28-ESR 的疾病活动谱也显示出相似的趋势。
我们发现 RA-ILD 患者血清 CHI3L1 水平升高，提示其可能作为一种非侵入性检测 RA-ILD 的生物标志物。
