ABSTRACT: BACKGROUND:Systemic sclerosis (SSc), a life-threatening autoimmune disease characterized by vasculopathy. Numerous SSc patients demonstrate gastrointestinal (GI) involvement but the delicate GI bleeding risk remains sparse. We aimed to explore the role of SSc in determining the long-term risk of GI bleeding, including bleedings of upper (peptic and non-peptic ulcers) and lower GI tracts. METHODS:Patients with SSc diagnosis were identified from the Catastrophic Illness Patient Database and the National Health Insurance Research Database from 1998 to 2007. Each SSc patient was matched with five SSc-free individuals by age, sex, and index date. All individuals (case = 3665, control = 18,325) were followed until the appearance of a GI bleeding event, death, or end of 2008. A subdistribution hazards model was assessed to evaluate the GI bleeding risk with adjustments for age, sex, and time-dependent covariates, comorbidity, and medications. RESULTS:The incidence rate ratios of GI bleeding were 2.38 (95% confidence interval [CI], 2.02-2.79), 2.06 (95% CI, 1.68-2.53), and 3.16 (95% CI, 2.53-3.96) for over-all, upper, and lower GI bleeding events in SSc patients. In the competing death risk in the subdistribution hazards model with time-covariate adjustment, SSc was an independent risk factor for over-all GI bleeding events (subdistribution hazard ratio [sHR] 2.98, 95% CI, 2.21-4.02), upper GI bleeding events (sHR 2.80, 95% CI, 1.92-4.08), and lower GI bleeding events (sHR 3.93, 95% CI, 2.52-6.13). CONCLUSION:SSc patients exhibited a significantly higher risk of over-all and different subtype GI bleeding events compared with the SSc-free population. The prevention strategy is needed for these high GI bleeding risk groups.