A Self-controlled Study Of Leflunomide In The Treatment Of Rheumatoid Arthritis With Interstitial Lung Disease

Objective:Leflunomide(LEF)has been widely used in the treatment of Rheumatoid arthritis(RA),but whether LEF is suitable for the treatment of RA with Interstitial lung disease(ILD)is unclear.The aim of this study is to investigate the therapeutic effect of LEF on RA patients with ILD and RA patients without ILD,and its effect on imaging progression,so as to provide a clinical basis for drug selection of the disease.Methods:In this single-center study,we retrospectively collected RA patients with ILD and RA patients without ILD treated with LEF.The study was divided into two groups,RA with ILD group and RA without ILD group.The clinical data of the two groups were analyzed,including general information,serological manifestations,disease activity indicators,chest high-resolution CT,joint imaging findings,and adverse reactions after medication.Measurement data:obey normal distribution,described by mean±standard deviation(x±s);The normal distribution was not followed,and the median(lower quartile,upper quartile)was used to describe the M(P25,P75).The comparison between baseline and follow-up period was performed by paired design t test and paired design signed rank sum test.Count data were described by frequency and percentage,and the comparison between baseline and follow-up period was analyzed byχ~2test,adjustedχ~2test,or Fisher’s exact test.Results:1.RA-ILD group:Among the 66 patients with RA-ILD,38 were male,accounting for 57.6%,and 28were female,accounting for 42.4%The proportion of male patients was higher than that of female patients.The average age was 65 years,and the average disease duration was 86months.29 cases(43.9%)had a history of smoking.After LEF treatment,the number of joint pain and swelling in the RA-ILD group was significantly lower than that in the baseline period(P<0.05).The arthritis disease activity assessment in the RA-ILD group showed that the rheumatoid arthritis in the RA-ILD group was mostly medium/high activity at baseline.After LEF treatment,most RA-ILD patients achieved disease remission/low activity,and the differences were statistically significant(DAS28ESR,CADI,SDAI P<0.001);ESR and CRP after LEF treatment were significantly lower than those at baseline(P<0.001);There was no significant difference in CCP and RF before and after treatment;HRCT assessment:including radiological pattern,degree of lung involvement,and ILD score.UIP and NSIP were the common types of RA-ILD,accounting for 53.0%and39.4%,respectively.OP and LIP were less common:4.5%and 3.0%,respectively.The analysis of the degree of lung involvement showed that the degree of lung involvement was limited(46,69.7%),moderate(12,18.2%)and extensive(8,12.1%).The median HRCT score before and after treatment was 4,and the difference was not statistically significant(P>0.05);In RA-ILD group,there were 2 cases(3.0%)of elevated liver enzymes,1 case(1.5%)of pruritus,2 cases(3.0%)of back pain,and no other adverse reactions.2.RA alone group:Among the 108 RA patients,the proportion of female patients(75.9%)was significantly higher than that of male patients(24.1%).The mean age was 56 years and the mean disease duration was 106 months.Eighteen patients(17.0%)had a history of smoking;According to the arthritis disease activity assessment in the RA group,most of the RA patients in the baseline RA group were moderately/highly active.After LEF treatment,most RA patients achieved disease remission/low activity,and the differences were statistically significant(DAS28ESR,CADI,SDAI P<0.001);ESR and CRP after LEF treatment were significantly lower than those at baseline(P<0.001);There was no significant difference in CCP and RF before and after treatment;The chest CT and HRCT images of 48 patients with RA alone group were collected in this study.No ILD and other pulmonary complications such as pulmonary infection were found in the RA-alone group at baseline and follow-up;In the RA-alone group,there were 7 cases(6.5%)with elevated liver enzymes,2cases(1.9%)with pruritus,and the incidence of other adverse reactions was low.Conclusions:1.After LEF treatment,most patients in RA-ILD group and RA-alone group achieved disease remission/low titer activity and decreased serum inflammatory markers.LEF has a good anti-inflammatory effect in RA-ILD group and RA-alone group.2.According to HRCT score,LEF could not aggravate the progression of interstitial pneumonia in RA-ILD patients.3.Chest CT and HRCT analysis showed that LEF could not induce ILD and other pulmonary complications in RA-alone group.