S3036 Systemic Sclerosis and Small Bowel Obstruction: A Comprehensive Analysis of Outcomes Using the TriNetX Global Health Database

Introduction: Systemic sclerosis (SSc) causes small bowel obstruction (SBO) through progressive smooth muscle atrophy and fibrosis, leading to hypoperistalsis and significant morbidity/mortality. Despite its clinical relevance, data on SBO outcomes in SSc remain limited. This study compares these outcomes using a large multi-institutional database. Methods: This retrospective cohort study utilized TriNetX global research network from 146 healthcare organizations. Two cohorts were defined: adults ≥18 years with both SBO and SSc (Cohort A) and adults with only SBO (Cohort B). A comparative outcome analysis was performed evaluating all-cause mortality, sepsis, malnutrition, deep vein thrombosis/pulmonary embolism, gastrointestinal bleeding, bowel perforation, small intestinal bacterial overgrowth (SIBO), inpatient hospitalizations, and use of total parenteral nutrition (TPN), over a 20-year follow-up period (2005-2025). Propensity score matching was used to balance baseline demographic and clinical characteristics. Results: The study included 2,455 patients with both SSc and SBO (Cohort A) and 620,485 patients with only SBO (Cohort B). After 1:1 propensity score matching, 2,323 patients from each cohort were compared. Patients in Cohort A had higher all-cause mortality risk (30% vs 20%; RR 1.46, P < 0.001), and poorer survival (61% vs 73%; χ² = 52.58, P < 0.001). Patients in Cohort A were 64% more likely to become malnourished (RR 1.64, P < 0.0001), with 71% remaining malnutrition-free compared to 83% in Cohort B by the end of the study period (χ² = 42.75,P < 0.001). Patients with SSc were 24% more likely to develop sepsis (RR 1.24, P < 0.001), with 79% remaining sepsis-free compared to 84% in Cohort B at the end of the study period (χ² = 7.99, P = 0.005). Although absolute risks of DVT/PE and GI bleeding were similar between cohorts, cumulative incidence of these events was significantly higher in Cohort A (for DVT/PE: χ² = 4.74, P = 0.03; for GI bleeding: χ² = 4.77, P = 0.03). No significant differences were observed in the risk of bowel perforation, SIBO, or need for TPN between the 2 groups, and survival probabilities at the end of follow-up were similar. Patients with SSc had more inpatient hospitalizations (mean 8, SD = 13 vs 7, SD = 11; t = 2.96, P = 0.003). Conclusion: SSc patients with SBO had worse outcomes than non-SSc patients, including higher risks of death, malnutrition, sepsis, and more frequent hospitalizations. This highlights need for close monitoring and proactive management. Further research is needed to explore these associations.