Application of antithrombotic drugs and risk factor analysis in ICU patients with lower gastrointestinal bleeding from MIMIC-IV

Objective This study aims to assess the effects of antithrombotic therapy on the outcomes of lower gastrointestinal bleeding (LGIB) in ICU patients, focusing on in-hospital mortality, rebleeding, and length of hospital and ICU stays. Method This retrospective observational study utilized the MIMIC-IV 2.2 database, which includes 513 ICU patients with LGIB. Result The in-hospital mortality rate was 7.6%, and the rebleeding rate was 11.1%. The average Oakland risk score among the study population was 22.54. Multivariate Cox regression analysis identified the use of antiplatelet drugs as an independent protective factor for in-hospital mortality (HR = 0.37, 95% CI 0.15-0.90, p = 0.029). Patients on anticoagulants experienced significantly longer hospital stays (13.1 +/- 12.2 days vs. 17.4 +/- 12.6 days, p = 0.031) compared to those not using these drugs. Propensity score matching also supported these findings, indicating that antithrombotic therapy was associated with lower in-hospital mortality and longer hospital stays even after adjusting for factors like age, gender, and primary diagnosis. Conclusions Our analysis using various statistical methods, including propensity score matching and multivariate regression, confirms that use of antithrombotic drugs in 2.3 days, particularly antiplatelets, are associated with a lower risk of in-hospital mortality. However, they may increase the risk of rebleeding and extend hospital stays in certain subgroups.