POS0700 TREATMENT OF INTERSTITIAL LUNG DISEASE IN PATIENTS WITH PRIMARY SJOGREN SYNDROME: A SINGLE-CENTER RETROSPECTIVE ANALYSIS

Background:Interstitial lung disease (ILD) is one of the main contributor to morbidity and mortality in patients with primary Sjogren syndrome (pSS), and whether immunosuppressive treatments are effective for pSS-ILD is uncertain. Cyclophosphamide (CYC) and rituximab (RTX) are effective in stabilizing pulmonary function in patients with ILD caused by systemic sclerosis, inflammatory myositis, and rheumatoid arthritis1,2. Reports regarding the treatment response for cyclophosphamide or rituximab in pSS-ILD patients are lacking.Objectives:To investigate whether add-on CYC or RTX in addition to steroid and oral DMARDs leads to greater improvement in pulmonary function test than conventional treatment in patients with pSS-ILD with impaired baseline pulmonary function.Methods:pSS-ILD patients with ILD confirmed by a chest computed tomography were screened. Those with imparied baseline pulmonary function test (FVCResults:This study enrolled 22 patients. The median age of these patients was 65. Among them, 68% were female and 18% were smokers. The median baseline FVC was 63.5% and the median DLCO was 54.4%. The predominant CT pattern was NSIP (54%), followed by UIP (22%), LIP (13.6%) and OP (9%) (table 1).Five patients received steroid and oral DMARDs alone (hydroxychloroquine +/- azathioprine), while 17 patients received add-on CYC and/or RTX (8 patients received CYC, 3 received RTX, and 6 received CYC and RTX). There was no significant difference in baseline characteristic between these two groups (table 1).With a median follow-up period of 9.8 months (interquartile range 7.6 - 13.4 months) after treatment, the FVC improved significantly from 61.3% to 65.5% (p=0.013) in CYC/RTX group, while the FVC improvement was not significant in steroid/oDMARD group (figure 1A). In CYC/RTX group, patients with non-UIP pattern (NSIP, LIP and OP) on chest CT had significant FVC improvement (p=0.021), contrasting to the patients with UIP pattern on chest CT (figure 1B).Conclusion:In pSS patients with ILD and impairment of pulmonary function at baseline (FVCReferences:[1]Wells AU, Denton CP. Interstitial lung disease in connective tissue disease--mechanisms and management. Nat Rev Rheumatol. 2014 Dec;10(12):728-39.[2]Gao Y, Moua T. Treatment of the Connective Tissue Disease-Related Interstitial Lung Diseases: A Narrative Review. Mayo Clin Proc. 2020 Mar;95(3):554-573.Table 1.Baseline characteristics of patients with Sjögren’s syndrome and interstitial lung diseaseTotal(n = 22)Steroid/oDMARDs (n = 5)Add-on CYC/RTX(n = 17)Comparison between two groups (p-value)Age, year, median (IQR)65.1 (61.7 - 69.1)64 (64.6 - 67.4)65.6 (61.6 - 69.2)0.88Female sex, n (%)15 (68%)4 (80%)12 (70%)1.00Smoking, n (%)4 (22%)0 (0%)4 (21%)0.54Baseline FVC, % of predicted value, median (IQR)63.6% (53.8 - 68.2)63.9% (63.7 - 67.5)61.3% (50.2 - 68.2)0.43Baseline DLCO, % of predicted value, median (IQR)54.4% (39.4 - 66.4)69.1% (57.8 - 75.5)52.1% (38.5 - 58.1)0.12CT pattern, n (%)NSIP - 12 (54%)NSIP 1 (20%)NSIP - 11 (65%)-UIP - 5 (22%)UIP 1 (20%)UIP - 4 (24%)LIP - 3 (13.6%)LIP 2 (40%)LIP -1 (6%)OP - 2 (9%)OP 1 (20%)OP -1 (6)UIP pattern, n (%)5 (22%)1 (20%)4 (24%)1.00CYC, cyclophosphamide; oDMARDs, oral DMARDs; RTX, rituximabFigure 1.FVC change before and after the immunosuppressive treatmentDisclosure of Interests:None declared