POS0871 CHARACTERISTICS OF INTERSTITIAL LUNG DISEASE IN PATIENTS WITH SYSTEMIC SCLEROSIS DURING LONG TERM FOLLOW-UP, SINGLE CENTER EXPERIENCE
Authors: S. Keret, Y. Braun-Moscovici, M. Yigla, V. Shataylo, L. Guralnik, A. Balbir-Gurman
Journal: Annals of the Rheumatic Diseases (2021)

Background: ILD is one the leading causes of morbidity and mortality in patients with SSc. Diagnosis of SScILD is based on signs of fibrosis on chest x-rays or HRCT. Particular measurement of lung volumes by FVC and in gas exchange by DLCO supports the diagnosis. Associations between clinically significant SSc ILD and male gender, age, DcSSc, topoisomerase antibodies, low FVC at baseline, widespread lung involvement on baseline HRCT, and higher decline rate of FVC and DLCO during followup were reported. A standardized approach to assessing and treating SSc and SScILD in particular have been proposed. Main treatment regimens include cyclophosphamide and mycophenolate mofetil; recently antifibrotic drug nintedanib showed significant efficacy in hindering FVC decline rate in patients with SSc ILD. The data on survival changes in SSc generally and SScILD are conflicting. Objectives: To analyze demographic and clinical features and mortality of patients with SSc ILD. Methods: A retrospective study on Rambam Health Care Campus prospective cohort of SSc patients fulfilled ACR and EULAR Classification Criteria 2013 for the period between January 2000 and September 2020 was performed. Patients were recruited at one of their early visits to the clinic. The majority of recruited patients were included into EUSTAR prospective cohort 042, since 2004 the Rheumatology Institute at Rambam is affiliated to EUSTAR registry project. Data on patients not registered in EUSTAR database but treated at our institution was extracted via hospital electronic records. Patients with lung involvement underwent baseline and annual HRCT and pumonary function tests in addition to clinical assessment during their visit to combined rheumatology-pulmonology clinic. We registered age, gender, ethnicity, date of SSc diagnosis and ILD diagnosis, disease duration, SSc subset, pulmonary, cardiac, renal, and muscle involvement, treatment used, autoantibodies, FVC, DLCO, HRCT and pulmonary artery pressure. Statistical analysis included t-test, Pearson’s Chi-squared test, Fisher’s test, and Cox Regression analysis with p value less than 0.05 as significant. Results: Among 446 SSc patients (female 82.3%, mean age 46.5 and disease duration 11.6 years, DcSSc 39.2%; 27.4% dead during follow-up) 141 patients had ILD. Comparison between patient with ILD and witout ILD showed significant differences in term of nationality (Arabs 34% vs 18.7%), SSc related death 78.3% vs 50.7%), DcSSc (68.8% vs 25.6%), topoisomerase antibodies (61.7% vs 24.9%), myopathy (21.3% vs 10.2%) and pulmonary hypertension (34.8% vs 22.3%). Significantly more SSc ILD patients were treated with cyclophosphamide, mycophenolate mofetil and azathioprine. Survival Kaplan-Meier curve patiets demonstrate reduced survival in patients with ILD (p&lt;0.01). Five years survival rates between years 2000 and 2015 have not changed significant. Mortality risk assessed with Cox regression analysis in the whole group was significantly higher in males, Arabs, DcSSc, elder age, heart and muscle involvement, and treatment with CYC. In the ILD group, the mortality was significantly higher in Arabs (3.3 times), elder age (8.9 times), presence of PAH (3.1 times) and treatment with CYC (2.8 times) compared to patients without ILD. Conclusion: In our SSc cohort, ILD affected about third of patients and had major impact on patients’ outcome. Male gender, Arab nationality, elder age, DcSSc, topoisomerase antibodies, heart and muscle involvement were significantly associated with worst prognosis. Despite active approach to assessing and treatment, survival rates of patients with SSc and SSc-ILD have not improved in last decades. Enrichment of the cohort with severe patients to a tertiary center due to reference bias and low efficacy of existed immunomodulatory drugs in SSc and in SSc related ILD particularly, could explain our results. Disclosure of Interests: None declared