Pos0843 predictors of interstitial lung involvement and timing of onset in systemic sclerosis: our experience at a third-level hospital

Background Interstitial lung disease (SSc-ILD) and pulmonary hypertension are the leading causes of death in patients with systemic sclerosis (SSc). Identifying SSc-ILD development and initiating treatment is essential to optimize therapeutic benefit. Objectives We aimed to identify predictors of SSc-ILD and compared early (<5 years from diagnosis) versus late (>5 years from diagnosis) onset. Methods We conducted a retrospective cohort study by including patients diagnosed with SSc from 1980 to 2020 followed in our unit and compared the clinical profile of patients with SSc-ILD to control SSc-non-ILD patients. Demographic features, clinical and immunological characteristics, baseline pulmonary function and capillaroscopy data were retrieved. Logistic regression modelling was run to identify factors associated with SSc-ILD development. Factors associated with ILD were then determined as factors associated with early or late onset using multivariate analysis. Bonferroni correction was used to limit Type I errors. Results We have included 103 patients from our patient registry from 1980 to 2021 (42% with SSc-ILD). Logistic regression identified risk factors associated with increased or decreased odds ratio for developing ILD is summarized in Table 1. Smoking history, male sex, the presence of myositis, anti-Scl70 and anti-Ro52 positivity, baseline pulmonary function including FVC and DLCO, mMRC (Modified Medical Research Council) dyspnea scale>2, mMSS (Modified Rodnan Skin Score), and late pattern in capillaroscopy were identified as SSc-ILD predictors. Older age at SSc diagnosis, the presence of telangiectasias and smoking status were correlated with of SSc-ILD onset before 5 years, while male gender, the presence of myositis and antiphospholid antibodies were correlated with late-onset SSc-ILD. Table 1. Significant logistic regressions for predictors for SSc-ILD Predictor OR (95% CI ) P value Male 2.8 (1.16-6.8) 0.02 Smoking history 2.15 (1.33-3.46) 0.001 Diffuse cutaneous involvement 10.4 (2.2-48.3) 0.003 Raynaud duration 0.89 (0.79-1.0) 0.04 Myositis 3.45 (1.09-10.9) 0.03 Anti-Scl70 5.45 (2.02-14.7) 0.001 Anti-Ro52 3.37 (1.49-9.45) 0.002 FVC 0.97 (0.91-0.98) 0.03 DLCO 0.96 (0.93-0.98) 0.003 mMSS 3.73 (1.64-8.5) 0.01 mMRC>2 2.01 (1.52-4.2) 0.04 Late capilaroscopy pattern 2.3 (1.02-5.27) 0.04 Early onset SSc-ILD β value P value Older age at onset 0.47 0.0017 Telangiectasias 0.29 0.04 Smoking stauts 0.37 0.02 Late onset SSc-ILD β value P value Male gender 0.57 0.001 Myositis 0.34 0.02 Antiphospholipid antibodies 0.31 0.04 Conclusion We identified 10 factors significantly associated with risk of developing SSc-ILD: smoking, male sex, diffuse cutaneous involvement, the presence of myositis, shorter Raynaud duration to SSc diagnosis, anti-Scl70 and anti-Ro52 positivity and baseline pulmonary function (lower baseline DLCO and FVC increasing risk) and late capillaroscopy pattern and identified predictors for early and late-onset SSc-ILD. References [1]Onat A, Zengin O, Balci M, et al AB0670 The Survival and Prognostic Factors of Patients with Systemic Sclerosis: Experience of Two Centers. Annals of the Rheumatic Diseases 2015;74:1122. [2]Kapralik J, Morton R, Farooqi M, Beattie K, Hambly N, Larche M. Predictors of ILD Development and Timing of Onset in Systemic Sclerosis: A Canadian Cohort [abstract]. Arthritis Rheumatol. 2021; 73 (suppl 10). Disclosure of Interests None declared