A novel prediction tool for mortality in patients with acute lower gastrointestinal bleeding requiring emergency hospitalization: a large multicenter study.

The study aimed to identify prognostic factors for patients with acute lower gastrointestinal bleeding and to develop a high-accuracy prediction tool. The analysis included 8254 cases of acute hematochezia patients who were admitted urgently based on the judgment of emergency physicians or gastroenterology consultants (from the CODE BLUE J-study). Patients were randomly assigned to a derivation cohort and a validation cohort in a 2:1 ratio using a random number table. Assuming that factors present at the time of admission are involved in mortality within 30 days of admission, and adding management factors during hospitalization to the factors at the time of admission for mortality within 1 year, prognostic factors were established. Multivariate analysis was conducted, and scores were assigned to each factor using regression coefficients, summing these to measure the score. The newly created score (CACHEXIA score) became a tool capable of measuring both mortality within 30 days (ROC-AUC 0.93) and within 1 year (C-index, 0.88). The 1-year mortality rates for patients classified as low, medium, and high risk by the CACHEXIA score were 1.0%, 13.4%, and 54.3% respectively (all P < 0.001). After discharge, patients identified as high risk using our unique predictive score require ongoing observation.