In the present study, we evaluated whether INBS is effective in predicting 30-day mortality in NVUGIB patients and determined whether it can be helpful in predicting re-bleeding or admission duration. INBS was superior to other pre-endoscopy risk scoring systems in predicting 30-day mortality.
AUGIB is a common medical emergency associated with high morbidity and 30-day mortality rates.1,16 More than 70% of AUGIB cases are NVUGIB, with GUs or DUs being the commonest. Mallory-Weiss syndrome, Dieulafoy’s ulcer, angiodysplasia, and cancer-related bleeding are also causes of NVUGIB.17 The use of anti-ulcer drugs, such as Helicobacter pylori eradication therapy and proton-pump inhibitors, was expected to reduce peptic ulcers and decrease the mortality rate of NVUGIB patients, but the mortality rate was still as high as 6%–14% owing to population aging and use of antiplatelet drugs, anticoagulants, and non-steroidal anti-inflammatory drugs.18–21 In these NVUGIB patients, timely hemostatic endoscopic procedures are important for survival improvement. For a successful treatment, assessing the hemodynamic status and appropriate risk measurement are necessary. Thus, classifying high-risk NVUGIB patients who have arrived at the ER using a highly efficient scoring system is important to help predict prognosis.22
A variety of indicators (AIMS65,10,11 GBS,9 Pre-RS,8 PNED12) have been developed and evaluated to assess the risk of NVUGIB. Hyett et al. found that the AIMS65 score was superior to GBS in predicting death, but the GBS was better in predicting the need and the number of packed red blood cell transfusions.23 In a cohort study of 424 participants, AIMS65 was also superior to GBS and Pre-RS in predicting hospital mortality, ICU admission, and loss of conscious.24 In a European study, the usefulness of GBS, Pre-RS, and AIMS65 in patients with UGIB was assessed; however, there was no difference in mortality or re-bleeding frequency among the three scoring systems, and GBS was the best predictor of transfusion.25 In another European study of 309 patients with UGIB, AIMS65, GBS, and Pre-RS were reported to be similar when predicting patient mortality; however, the need for endoscopic intervention was better predicted by AIMS65 and GBS.26 In a study on the utility of GBS and AIMS65 conducted in the United States and involving 165 patients with NVUGIB aged ≥65 years, GBS was superior to AIMS65 in predicting mortality.15 Evaluation of the usefulness and predictability of the scoring system for assessing the prognosis of NVUGIB varies according to each study. The recent INBS13 was developed to predict the 30-day mortality risk of patients with NVUGIB and has been shown to predict mortality better than the previous scoring systems. It is a predictive scoring system similar to the Pre-RS and PNED scores. However, INBS provides clear criteria for cirrhosis, differentiation of ASA scores according to hemodialysis, and blood tests to assess liver and renal functions. Unlike previous scoring systems, this included subjective factors of medical staff to score liver, renal, and heart failures. It is simple and easy to apply as it classifies and score items through objective indicators.
Our research suggests several strengths based on this new scoring system. First, this study validated INBS against the Pre-RS, GBS, AIMS65, and PNED risk stratification scores for predicting 30-day mortality. INBS was superior to other pre-endoscopy risk scores in predicting 30-day mortality. AIMS65, PNED, and Pre-RS showed higher mortality predictions with an AUROC >0.8, but it had lower values compared to INBS. Secondly, variables considered as risk factors in each scoring system were confirmed in this study. In the multivariate analysis, an ASA score of 4, ARDS, disseminated malignancy, creatinine, albumin, syncope at first visit, and failure of endoscopic treatment within 24 hours of the first visit were identified as risk factors for death in NVUGIB patients. The risk of death due to underlying disease factors, aggravation of liver and kidney diseases, and failure of endoscopic treatment at the first visit were confirmed. The significant death risk factors in this study were similar to the death risk factors already reflected in INBS. INBS has proposed criteria to identify liver and renal failures through liver cirrhosis, decreased albumin levels, and increased BUN and creatinine levels. The severity of the underlying disease was scored using the ASA classification. Thirdly, we classified the patients into the high- and low-to-moderate-risk groups based on the INBS cutoff value of >7. The cut-off value was the same to that published in a previous study of ≥8 for the high-risk group.16 In our study, we showed that the high INBS group had a relatively long hospital stay and high re-bleeding and endoscopic hemostasis failure rates. The cause of death from bleeding was one of the predictable outcomes if the patient was unable to tolerate hemostatic treatment due to poor general condition or bleeding from cancer and massive bleeding from the large vessels. Therefore, classification of patients using INBS is relatively expected to be used as a tool to increase the probability of successful hemostasis and to shorten the hospitalization period through rapid endoscopic treatment and intensive monitoring.
Korea’s tertiary medical care institutions have a tendency to promptly and actively perform endoscopy in patients. Therefore, it is necessary for the doctors who performed endoscopy to have a classification standard or score to help determine the appropriate time of endoscopy and to predict the prognosis of NVUGIB patients. Using INBS, identification of patients with a high risk of death is possible, allowing targeted management and interventions that may improve outcome.
This study has some limitations. First, the present investigation was a retrospective, single-center study, which can be a confounding factor. Therefore, a larger sample size and a prospectively designed study are needed to confirm the effectiveness of INBS. Second, this is an observational study, which focused on a high-risk mortality factor and classified high-risk patients. However, the criteria for low-risk patients with low scores were not established, and neither the criteria for the need for endoscopic treatment nor those for outpatient follow-up were presented. Given the nature of the tertiary medical institutions, most patients visiting the ER with AUGIB are often referred from other medical institutions because of the severity of the disease. Thus, doctors often think that endoscopy should be performed or patients want to undergo endoscopy. Therefore, examining our study subjects is important to confirm the suitability of the score in selecting low-risk patients to receive outpatient treatment without endoscopy. In addition, the INBS scoring system is limited in its use as a criterion for selecting low-risk groups, because it weighs in identifying patients who are at risk of sudden aggravation or death from liver or kidney disease. However, further studies on the usefulness of early endoscopy and the feasibility of applying a second-look endoscopy according to the risk of this new scoring system may be needed.
In conclusion, INBS is useful for predicting 30-day mortality in patients with NVUGIB. Screening for high-risk groups using this new scoring system can also predict mortality, longer hospital admission, re-bleeding, and endoscopic hemostasis failure. The new scoring system enables a timely endoscopic approach and appropriate management, which can improve the prognosis of patients with NVUGIB. However, further prospective studies are necessary to validate the new scoring system in non-variceal bleeding.