Validation and modification of existing mortality prediction model for lower gastrointestinal bleeding: A retrospective study

Abstract Background Lower gastrointestinal bleeding (LGIB) often subsides by itself; however, in some cases, the bleeding does not stop and the patient’s condition worsens. Therefore, if the occurrence of severe lower gastrointestinal bleeding can be predicted in advance, it can be helpful for treatment. This study aimed to evaluate variables related to mortality from LGIB and to propose a scoring system. Methods This retrospective study reviewed the medical records of patients who visited the emergency room with hematochezia between January 2016 and December 2020. Through regression analysis of vital signs, laboratory investigations, and hospital stay, variables related to LGIB-related mortality were evaluated. A scoring system was developed, and the appropriateness with an area under the receiver operating characteristics curve (AUROC) was evaluated and compared with other existing models. Results A total of 932 patients were hospitalized for LGIB. Variables associated with LGIB-related mortality were the presence of cancer, heart rate of > 100 beats/min, blood urea nitrogen level of ≥ 30 mg/dL, an international normalized ratio of > 1.50, and albumin level of ≤ 3.0 g/dL. The AUROCs of CNUH-4 and CNUH-5 were 0.890 (p < 0.001; cutoff, 2.5; 95% confidence interval, 0.0851 − 0.929) and 0.901 (p < 0.001; cutoff, 3.5; 95% confidence interval, 0.869 − 0.933), respectively. Conclusions The model developed for predicting the risk of LGIB-related mortality is simple and easy to apply clinically. The AUROC of the model was better than that of the existing models.