Clinical Analysis Of Progressive Fibrosis In Rheumatoid Arthritis-related Interstitial Lung Disease

Objective:To explore the clinical characteristics of progressive fibrosis in rheumatoid arthritis-related interstitial lung diseases and to identify the risk factors of progressive fibrosis in patients with RA-ILD,so as to provide reference for early diagnosis.Methods:The clinical characteristics of 272 patients with RA-ILD hospitalized in the affiliated Hospital of Qingdao University from July 30,2012 to July 30,2020 were retrospectively analyzed and compared with those randomly selected from 200 patients with simple RA.The patients in RA-ILD group were divided into rheumatoid arthritis-associated interstitial lung disease progressive fibrosis group（PF-RA-ILD）and rheumatoid arthritis-associated interstitial lung disease non-progressive fibrosis group（NPF-RA-ILD）.The general condition,clinical manifestation,laboratory examination and imaging features of rheumatoid arthritis progressive fibrosis group were analyzed.The risk factors of ILD occurrence in RA patients and progressive fibrosis in RA-ILD were determined by Logistic regression analysis,and indicators such as sensitivity and specificity to evaluate the predictive value of risk factors were evaluated by drawing a curve and calculating the area under the curve.Result:RA-ILD group and simple RA group:1.Among the 1227 RA-ILD patients,115 were males（42.28%）,112 were females（49.34%）,and 85（31.25%）had a history of smoking.Among them,there were 48 male cases（24%）.Among the 200 patients in the RA-ILD group,48 were males（24%）,152（76%）were females and 30 cases（15%）had a history of smoking.The ratio of males,age,and smokers in the RA-ILD group were higher than those in the control group,and the difference was statistically significant（P<0.05）.2.The incidence of Raynaud’s phenomenon,cough,dyspnea,and fever in the RA-ILD group were higher than those in the RA-only group,while the incidence of muscle pain was lower than that in the RA-only group,and the difference was statistically significant（P<0.05）;RA-ILD group patients white blood cell count,neutrophil count,monocyte count,C-reactive protein（CRP）,erythrocyte sedimentation rate,rheumatoid factor（RF）,anti-cyclic citrullinated peptide（CCP）antibody,immunoglobulin M,immunity Globulin G,carbon dioxide partial pressure,and HCO₃^-were higher than those in the RA group,while the PH value,oxygen partial pressure,and oxygen saturation were lower than those in the RA group.The difference was statistically significant（P<0.05）;The utilization rate was significantly higher than that of the RA group alone.3.Through regression analysis,the independent risk factors for ILD in RA were determined to be age,smoking,Raynaud’s phenomenon,cough,monocyte count,anti-CCP antibody,carbon dioxide partial pressure,hormone only,hormone and immunosuppressant.4.Determine the cutoff value for the quantitative variables to distinguish between simple RA and RA-ILD,and clarify the predictive value of each variable in the diagnosis of RA-ILD.Among the quantitative variables,the AUC of the partial pressure of carbon dioxide is the largest.When the partial pressure of carbon dioxide is greater than38.75mm Hg,it is considered that simple RA and RA-ILD can be better distinguished.Followed by the concentration of anti-CCP antibodies,monocytes and age.PF group and non-PF group in RA-ILD patients:PF-RA-ILD group and NPF-RA-ILD group:1.Among the 227 RA-ILD patients,there are 112 patients with PF,including 70 males（62.5%）,42 females（37.5%）,58 patients（51.79%）with a history of smoking,and 160patients with NPF.There were 45 males（28.13%）,115 females（71.88%）,and 27 cases（16.88%）with a history of smoking.The proportion of males and the proportion of smokers in the PF-RA-ILD group were higher than those in the non-progressive fibrosis group,and the difference was statistically significant（P<0.05）.2.The incidence of joint pain in the PF-RA-ILD group was lower than that in the NPF-RA-ILD group.The difference was statistically significant（P<0.05）;the PH value,oxygen partial pressure,and oxygen saturation of the PF-RA-ILD group were all low In the NPF-RA-ILD group,the partial pressure of carbon dioxide and HCO₃^-was higher than that in the NPF-RA-ILD group,and the difference was statistically significant（P<0.05）.3.The incidence of ground-glass shadow（GGO）,subpleural ground-glass shadow,thickened lobular septum,thickened subpleural lobular septum,and subpleural honeycomb in the PF-RA-ILD group was higher than that in the NPF-RA-ILD group,with differences There is statistical significance（P<0.05）.4.Subpleural ground glass shadow is an independent risk factor for PF in RA-ILD.Conclusions:1.Older male patients with RA are more likely to have ILD.For older male patients,symptoms such as Raynaud’s phenomenon,cough,dyspnea,fever,etc.need to be alert to the possibility of ILD.For white blood cell count,neutrophil count,monocyte count,erythrocyte sedimentation rate,RF,anti-CCP antibody,immunoglobulin M,immunoglobulin G,and blood gas analysis,RA with elevated carbon dioxide partial pressure and decreased PH and oxygen partial pressure Patients should be followed up closely to be alert to the occurrence of ILD.2.Age,smoking,Raynaud’s phenomenon,cough,elevated monocytes,anti-CCP antibodies,carbon dioxide partial pressure and the use of hormones,hormones and immunosuppressants are independent risk factors for ILD in RA patients.According to the area under the ROC curve,the increase in carbon dioxide partial pressure is of greater significance in predicting the occurrence of ILD.3.Among RA-ILD patients,male patients who smoke are more likely to develop progressive fibrosis.The clinical manifestations are arthralgia and blood gas analysis showing elevated carbon dioxide partial pressure,and those with decreased PH and oxygen partial pressure may indicate the occurrence of progressive fibrosis.4.HRCT has become the standard for imaging evaluation of pulmonary fibrosis.The imaging manifestations include ground-glass shadow,thickening of the lobular septum,especially the subpleural ground-glass shadow,thickening of the interlobular septum,and subpleural honeycomb.RA-ILD patients need to be monitored.Whether there are signs of progressive fibrosis.5.Through Logistic regression multivariate analysis,it was found that subpleural ground glass opacity is an independent risk factor for the development of progressive fibrosis.