Supplementary Material for: Gastroesophageal Reflux Disease-Related Disorders of Systemic Sclerosis Based on the Analysis of 66 Patients

<b><i>Background/Aims:</i></b> Gastroesophageal reflux disease (GERD)-related disorders of systemic sclerosis (SSc) patients have not been adequately investigated. <b><i>Methods:</i></b> Sixty-six SSc patients (5 males and 61 females; 56.6 ± 14.6 years old) who underwent esophagogastroduodenoscopy were analyzed on the basis of 16 background factors. They were additionally compared with 116 matched non-SSc subjects controlling age, sex, and use of proton pump inhibitors (PPIs). <b><i>Results:</i></b> The mean disease duration of 66 patients was 5.1 ± 8.1 years, and their breakdown was as follows: 53 (80.3%) with GERD, 38 (57.6%) with GERD-related symptoms, and 20 (30.3%) with reflux esophagitis (RE; LA-A: 10, LA-B: 5, LA-C: 4, LA-D: 1). Use of PPI (<i>p</i> = 0.0455), complication of interstitial lung disease (<i>p</i> = 0.0242), and history of cyclophosphamide therapy (<i>p</i> = 0.0184) denoted significant association with GERD-related symptoms. Older age (<i>p</i> = 0.0211) was significantly associated with RE. None of GERD-related disorders showed any difference between 37 diffuse cutaneous SSc and 29 limited cutaneous SSc patients. The matched analysis indicated that SSc patients had higher prevalence of GERD (<i>p </i>< 0.0001), GERD-related symptoms (<i>p</i> = 0.0034), and RE (<i>p </i>= 0.0002). <b><i>Conclusion:</i></b> SSc patients tend to have worse GERD symptoms and severer RE. However, most SSc-associated factors did not show significant association with GERD-related disorders, indicating the difficulty in predicting GERD-related disorders among SSc patients.