血清KL-6水平对类风湿关节炎合并间质性肺病的预测及其与预后的关系

Prediction of serum KL-6 level in rheumatoid arthritis complicated with interstitial lung disease and its relationship with prognosis

目的:探讨血清KL-6水平对类风湿关节炎(RA)合并间质性肺病(RA-ILD)的预测及其与预后的关系。方法:选取2018年1月至2021年1月内蒙古医科大学附属医院收治的RA患者70例,依据其是否合并间质性肺病(ILD)分为RA-ILD组(34例)和RA组(36例),对两组患者的临床资料进行单因素分析,重点比较两组患者血清中KL-6表达水平及实验室指标、肺功能、影像学等相关性分析,多因素Logistic回归分析影响RA-ILD的危险因素。结果:两组患者性别、吸烟史、年龄及发病年龄、病程、DAS28、KL-6、WBC、UA、RF、抗CCP抗体、TLC%Pred、DLCO%Pred差异有统计学意义(P<0.05);RA-ILD组患者临床症状占比关节痛较为突出,HRCT表现胸膜粘连增厚较为突出;Spearson相关性分析显示,RA-ILD组患者血清KL-6水平与TLC%Pred、VC%Pred、DLCO%Pred呈显著负相关(P<0.05),与RF、抗CCP抗体水平呈显著正相关(P<0.05);与FEV1%Pred、FEV1/FVC无明显相关性(P>0.05);RA-ILD组患者治疗前KL-6表达水平显著高于RA组,治疗后差异无统计学意义(P>0.05);随访1年,RA-ILD组有6例患者死亡,经分析死亡组KL-6表达水平显著高于未死亡组(P<0.05);高龄、男性、吸烟、抗CCP抗体升高及KL-6升高是影响RA-ILD的独立危险因素(P均<0.05);血清KL-6预测ROC曲线下最大面积为0.802,95%置信区间为0.743~0.866,灵敏度、特异度分别为0.853、0.827,联合检测ROC曲线下最大面积为0.854,表明该模型预测能力较强。结论:RA-ILD组患者血清KL-6水平显著升高,KL-6可作为早期发现ILD的血清学指标,联合肺功能检测可更早发现ILD,早期诊断对于治疗及预后有重要意义。

Objective:To investigate the prognostic relationship between serum KL-6 level and rheumatoid arthritis(RA)combined with interstitial lung disease(RA-ILD).Methods:In Affiliated Hospital of Inner Mongolia Medical University from January 2018 to January 2021,seventy patients with RA were selected and divided into RA-ILD group(34 cases)and RA(36 cases)according to whether they were complicated with ILD,clinicopathological characteristics of the two groups of patients were analyzed by univariate analysis,focusing on the comparison of the expression level of KL-6 in the serum of the two groups and the correlation analysis with laboratory indexes,lung function and imaging,multivariate Logistic regression analysis risk factors affecting RA-ILD.Results:There were significant differences in gender,smoking history,age,age of onset,course of disease,DAS28,KL-6,WBC,UA,RF,anti-CCP antibody,TLC%Pred and DLCO%Pred between the two groups(P<0.05).In RA-ILD group,the proportion of clinical symptoms was more prominent,joint pain was more prominent,and the thickening of pleural adhesion was more prominent on HRCT;Spearson correlation analysis showed that the level of serum KL-6 in RA-ILD group was significantly negatively correlated with TLC%Pred,VC%Pred and DLCO%Pred(P<0.05);there was a significant positive correlation with RF and anti-CCP antibody levels(P<0.05);there was no significant correlation with FEV1%Pred and FEV1/FVC(P>0.05);expression level of KL-6 in RA-ILD group was significantly higher than that in RA group before treatment,and there was no significant difference after treatment(P>0.05);Followed up for one year,six patients died in RA-ILD group.The expression level of KL-6 in death group was significantly higher than that in non death group(P<0.05);multivariate Logistic regression analysis showed that old age,male,smoking,increased anti CCP antibody and KL-6 were independent risk factors for RA-ILD(P<0.05);the maximum area under the ROC curve predicted by serum KL-6 was 0.802,the 95%CI was 0.743~0.866,the sensitivity was 0.853,the specificity was 0.827,and the maximum area under the ROC curve detected jointly was 0.854,indicating that the prediction ability of the model was strong.Conclusion:Serum KL-6 levels in RA-ILD patients are significantly increased.KL-6 can be used as a serological index for early detection of ILD,and combined with lung function detection can detect ILD earlier.Early diagnosis is of great significance for treatment and prognosis.