ABS0279 TRENDS IN PULMONARY FUNCTION TESTS IN PATIENTS WITH SYSTEMIC SCLEROSIS ASSOCIATED ILD (SSc-ILD): INSIGHTS FROM THE GERMAN NETWORK FOR SYSTEMIC SCLEROSIS (DNSS)

<h2>Abstract</h2><h3>Background:</h3> Interstitial lung disease (ILD) is one of the leading causes of death in systemic sclerosis (SSc). The decline in forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLco) in patients with SSc-ILD seems to be highly variable, but systematic investigation is needed. The aim of this analysis was to determine the decline of FVC and DLco over time in patients with SSc-ILD from the registry of the German Network for Systemic Sclerosis (DNSS). <h3>Methods:</h3> Clinical data of 6,234 patients with SSc were collected in the German Network for Systemic Sclerosis registry. Patients who developed ILD during and had at least two measurements of FVC and DLco during follow up were included in the analysis. Disease progression was defined as ≥ 10% relative decline in FVC% pred. or ≥ 5 to < 10% decline in relative FVC pred. and 15% relative decline in DLCO% pred. from baseline. Change in FVC and DLco was analysed using a mixed model for repeated measures (MMRM) with random imputation of missing data and adjustment for a number of covariates. <h3>Results:</h3> 1313 patients with SSc-ILD and at least one measurement of FVC and DLco over time were included in the analysis. Mean follow-up time was 3.99 ± 1.79 years and 246 (19%) patients had disease progression. The observed all caused mortality in 417 patients with complete follow up was 6 (1.4%). Mean time to disease progression was 2.84 ± 1.72 years. The estimated average rate of decline in FVC % pred. was 7.33% per year in patients with ILD progression with a difference of 16.91% to non-progressors (p= <0.001). The estimated average rate of decline in DLco % pred. was 9.16% per year in patients with a difference of 12.09% to non-progressors (p= <0.001). Patients with progression were significantly older at time of ILD diagnosis compared to those who remained stable (50 ± 15 vs 47 ± 14, p=0.011). No differences between progressors and stable patients were observed in terms of BMI, smoking habits, antibody status, extension of skin involvement, prevalence of pulmonary hypertension, inflammatory markers, and treatment with steroids or immunosuppressants. <h3>Conclusion:</h3> Disease progression in SSc-ILD patients seems to occur within the first 5 years after ILD diagnosis, with a similar trend in FVC and DLco decline. Clinical factors associated with ILD progression remain unclear. <h3>REFERENCES:</h3> <b>NIL</b>. <h3>Acknowledgements:</h3> <b>NIL</b>. <h3>Disclosure of Interests:</h3> Pia Moinzadeh Boehringer Ingelheim, Janssen, Advisory Board Almirall, Francesco Bonella: None declared, Jithmi Weliwitage: None declared, Gabriela Riemekasten Janssen, Boehringer Ingelheim, Lilly, Janssen, Boehringer, Jörg Henes ABBVIE, Astra Zeneca, Boehringer Ingelheim, BMS, Johnson&Johnson, Lilly, Novartis, Pfizer, Roche, SOBI, Otsuka, EUSA, UCB, ABBVIE, Astra Zeneca, Boehringer Ingelheim, BMS, Johnson&Johnson, Novartis, SOBI, UCB, Norbert Blank Novartis, Boehringer, EUSA, MSD, Pfizer, Roche, Sanofi, SOBI, SOBI, Novartis, Marc Schmalzing BMS, Novartis, AbbVie, Astra Zeneca, Chugai/Roche, Janssen-Cilag, Alfasigma/Galapagos, Boehringer Ingelheim, Mylan, Onkowissen.de, EUSA-Pharma, Chugai/Roche, Hetal/Sandoz, Alfasigma/Galgapagos, Abbie, Janssen-Cilag, Boehringer Ingelheim, Onkowissen.de, EUSA Pharma, Astra Zeneca, Lilly, UCB, Gabriele Zeidler Lilly, Boehringer Ingelheim, Janssen-Cilag, Alfasigma, Amgen, Boehringer Ingelheim, Alexion, Claudia Günther: None declared, Annette Alberding: None declared, Ilona Jandova: None declared, Jan Ehrchen Bristol Myers, Squibb, Boehringer, Sobi, Astra Zeneca, Biogen/Janssen, La Roche Posey, Mylan, Galderma, Novartis, Sobi, Boehringer, Gernot Keyszer Boehringer Ingelheim, Roche and Chugai, Margitta Worm AbbVie, Aimmune, ALK, Allergopharma, Almirall, Amgen, Astra Zeneca, Bayer, Bencard, Bioprojet Pharma, Bristol-Myers Squibb, Boehringer Ingelheim, Galderma, Glaxosmithkline, Infectopharm, Leo, Lilly, Mylan,/Viatris, Novartis, Octapharma, Pfizer, Sanofi, AbbVie, Aimmune, ALK, Allergopharma, Almirall, Amgen, Astra Zeneca, Bayer, Bencard, Bioprojet Pharma, Bristol-Myers Squibb, Boehringer Ingelheim, Galderma, Glaxosmithkline, Infectopharm, Leo, Lilly, Mylan/Viatris, Octapharma, Pfizer and Sanofi, Alexander Kreuter Boehringer Ingelheim, Ulf Müller-Ladner: None declared, Aaron Juche: None declared, Jörg Distler AbbVie, Active Biotech, Anamar, ARXX, AstraZeneca, Bayer Pharma, Boehringer Ingelheim, Calliditas Therapeutics, Celgene, Galapagos, Genentech, GSK, Inventiva, Janssen, Novartis, Pfizer, Roche and UCB. JHWD has received research funding from Anamar, Argenx, ARXX, BMS, Bayer Pharma, Boehringer Ingelheim, Cantargia, Celgene, CSL Behring, Galapagos, GSK, Inventiva, Kiniksa, Lassen, Sanofi-Aventis, RedX, UCB, CEO of 4D Science and Scientific Lead of FibroCure, AbbVie, Active Biotech, Anamar, ARXX, AstraZeneca, Bayer Pharma, Boehringer Ingelheim, Calliditas Therapeutics, Celgene, Galapagos, Genentech, GSK, Inventiva, Janssen, Novartis, Pfizer, Roche and UCB. JHWD has received research funding from Anamar, Argenx, ARXX, BMS, Bayer Pharma, Boehringer Ingelheim, Cantargia, Celgene, CSL Behring, Galapagos, GSK, Inventiva, Kiniksa, Lassen, Sanofi-Aventis, RedX, UCB, Nicolas Hunzelmann Boehringer Ingelheim, Leo, Michael Kreuter Boehringer Ingelheim, Boehringer Ingelheim. © The Authors 2025. This abstract is an open access article published in Annals of Rheumatic Diseases under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). 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