Comorbidities Associated with Worse Outcomes Among Inpatients Admitted for Acute Gastrointestinal Bleeding

Background Multimorbidity increases healthcare resource utilization. Little is known on specific comorbidity combinations. Aims To identify comorbidities associated with increased resource utilization among inpatients admitted for gastrointestinal bleeding (GIB). Methods This retrospective cross-sectional study, 1/2010–5/2018 at the University Hospital Zurich, Switzerland, analyzed electronic health records of patients with upper (UGIB) and lower (LGIB) GIB, focusing on length of stay (LOS) and 30-day readmissions for resource use and clinical outcomes, investigated by multivariable regression adjusted for antithrombotics. Results Of 1101 patients, 791 had UGIB and 310 LGIB, most often melena and bleeding diverticula, respectively. In UGIB, thromboembolic events showed a trend toward 27% increased LOS (1.27; 95% confidence interval [CI] 1.00–1.61), antithrombotics independently associated with 46% increased LOS (1.46; 95% CI 1.32–1.62). Cancer (odds ratio [OR] 2.86; 95% CI 1.68–4.88) independently associated with 30-day readmissions, anemia showed a trend (OR 1.68; 95% CI 1.00–2.84). In LGIB, none of the investigated comorbidities associated with increased LOS, but antithrombotics independently associated with 25% increased LOS (1.25; 95% CI 1.07–1.46). Atrial fibrillation/flutter (OR 2.69; 95% CI 1.06–6.82) and cancer (OR 4.76; 95% CI 1.40–16.20) associated strongly with 30-day readmissions. Conclusions In both groups, cancer associated with 30-day readmissions, antithrombotics with increased LOS. Thromboembolic events and anemia showed clinically important trends in UGIB. Atrial fibrillation/flutter associated with 30-day readmissions in LGIB. Prospective studies are needed to investigate these complex multimorbid populations and establish appropriate guidelines.