Gastroesophageal reflux disease is associated with a more severe interstitial lung disease in systemic sclerosis in the EUSTAR cohort

Objectives Gastroesophageal reflux disease (GERD) is frequent in systemic sclerosis (SSc) and could predict progression of interstitial lung disease (ILD). We aimed to analyse (1) the prevalence of GERD among SSc-ILD patients, (2) its association with disease characteristics and (3) predictive factors for ILD progression in SSc-ILD patients with GERD. Methods SSc patients from the EUSTAR database with ILD were included. GERD was labelled as present if reflux/dysphagia was reported at the baseline visit or before. Disease characteristics of patients with and without GERD were compared at baseline. ILD progression was defined as relative FVC decline ≥10% or relative FVC decline between 5–9% in association with relative DLCO decline of ≥15% over 12 ± 3 months of follow-up. Prognostic factors for ILD progression, overall survival and progression-free survival in SSc-ILD patients with GERD were tested by multivariable Cox regression. Results A total of 5462 SSc-ILD patients were included, 4400 (80.6%) had GERD. Patients with GERD presented more frequently with diffuse cutaneous SSc (OR: 1.44 [1.22–1.69], <em>P</em> < 0.001) and more severe lung involvement with lower FVC (85.8 ± 22.1 <em>vs</em> 90.2 ± 20.1, <em>P < </em>0.001), lower DLCO (60.8 ± 19.7 <em>vs</em> 65.3 ± 20.6, <em>P < </em>0.001) and worse performance at the 6-min walking test. Female sex (HR: 1.39 [1.07–1.80], <em>P</em> = 0.012) and older age (HR: 1.02 [1.01–1.03], <em>P < </em>0.001) independently predicted ILD progression in SSc-ILD patients with GERD. Conclusion SSc-ILD patients with GERD appear to suffer from a more severe SSc disease. In this population, female sex may be considered a risk factor for ILD progression.