To investigate the prognostic risk factors associated with acute lower gastrointestinal bleeding, construct a risk score and validate its predictive ability.

A retrospective analysis was conducted on the clinical data of 754 patients who were hospitalized for acute lower gastrointestinal bleeding at the First Medical Center and the Fourth Medical Center of the Chinese People's Liberation Army General Hospital from January 2015 to December 2020. After excluding the cases that did not meet the criteria, a total of 355 patients were included in the training set. These patients were divided into the safe discharge group (n=197) and the non-safe discharge group (n=158) based on whether they were discharged safely. From January 2021 to October 2023, 235 patients who were hospitalized and treated for acute LGIB were prospectively collected. After excluding the patients who did not meet the criteria, a total of 133 patients were finally included to establish the validation set. Univariate analysis and multivariate Logistic regression were used to identify the independent risk factors influencing safe discharge. A risk score was constructed, and the predictive value of this score was evaluated using receiver operating characteristic curve.

Through univariate analysis and multivariate Logistic regression analysis, it was found that history of liver disease, history of lower gastrointestinal bleeding, fresh bleeding, decrease in hemoglobin, and decrease in albumin were independent risk factors affecting safe discharge (P<0.05). The area under the risk score curve constructed based on these factors was 0.827, which was superior to the prediction models such as the Oakland score.

History of liver disease, history of lower gastrointestinal bleeding, fresh bleeding, decreased hemoglobin, and decreased albumin are independent risk factors affecting the safe discharge of patients with acute lower gastrointestinal bleeding. The risk score constructed based on these factors has a high predictive value for the safe discharge of patients and is helpful for the prognosis risk assessment of patients with acute lower gastrointestinal bleeding.