Investigators aim to conduct a large-scale, prospective cohort study in the Greater Bay Area of South China. Investigators aim to identify consecutive patients with AUGIB in the area over a 2-month period in the second quarter of 2025.

This study covers the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) as well as the western, eastern, and northern regions of Guangdong Province. It comprises of 2 Special Administrative Regions of Hong Kong and Macao and 21 municipalities in Guangdong Province (Guangzhou, Shenzhen, Foshan, Dongguan, Zhongshan, Zhuhai, Jiangmen, Zhaoqing, Huizhou, Shantou, Chaozhou, Jieyang, Shanwei, Zhanjiang, Maoming, Yangjiang, Yunfu, Shaoguan, Qingyuan, Meizhou, Heyuan). The total population of the Guangdong-Hong Kong-Macao area is estimated to be 135.24 million. Investigators aim to understand the current epidemiology of AUGIB in South China by collecting patient characteristics, the care model and management strategies including the use of endoscopy, interventional radiology and surgery, and the associated mortality.

The goal is to identify areas for improving patients' outcomes and to reduce mortality. The audit also provides a reference standard for future audits and a comparison to a minimal international standard.

Acute Upper gastrointestinal bleeding (AUGIB) remains a common medical emergency. Although the annual incidence of AUGIB has decreased from approximately 100 per 100,000 adults in the 1990s to 61-78 per 100,000 persons in 2009-2012, the 30-day mortality rate remains as high as 11%. The overall etiology and epidemiology of acute UGIB have undergone significant changes. The widespread eradication of H. pylori, the use of safer non-steroidal anti-inflammatory drugs (NSAIDs), and the use of proton pump inhibitors (PPIs) have reduced the incidence of bleeding peptic ulcers. The increasing prevalence of alcohol-related liver disease, common usage of anticoagulant or antiplatelet therapy, and an aging population (with associated co-morbidities) often worsen the prognosis. Overall, in the management of patients with AUGIB, the diagnostic and treatment methods such as endoscopic hemostasis have improved. This together with better access to both high-dependency care and interventional radiology can all contribute to better patient outcome in acute UGIB.

Epidemiologic studies in acute upper gastrointestinal hemorrhage from Asia mostly come from hospital-based studies with limited number of cases. These studies are largely retrospective in their nature. In China, there is a lack of population-based studies on AUGIB. There are also uncertainties in how these patients are managed especially over adoption of risk stratification tools, timely provision of care, the use of endoscopic hemostatic treatment, the use of drugs and red cell transfusion, and interventional radiology.

To understand the current epidemiology of AUGIB in the GBA, investigators aim to conduct a large-scale, prospective cohort study in the Greater Bay Area of South China. In this audit, Investigators identify patients with AUGIB admitted to participating hospitals and collect their demographic data, clinical presentation, management and outcomes The goal is to identify areas of opportunities in reducing mortality and improving patient outcomes.

This is a population based, unselected multicentre, prospective survey. Consecutive patients who present with signs of AUGIB, aged >18, admitted to the participating hospitals from August 1, 2024, to September 30, 2024, are identified. These patients include those admitted through the emergency department, and clinics, and patients who develop bleeding while being hospitalized for other reasons.

Up to forty hospitals receiving emergency admissions in the Guangdong-Hong Kong-Macao area in China are invited to participate in this study. Unselected acute UGIB adult patients (≥18 years old) admitted within a 2-month period in the second quarter of 2025 are identified. These patients are newly admitted patients from both the emergency department and clinics with overt signs of AUGIB, as well as patients who develop bleeding while hospitalized for other reasons At each center a "lead" consultant is designated to represent the hospital on the project. Lead PI and designated research staff identify cases by screening admission records to accident and emergency department and the admission wards, records in the endoscopy centre, interventional radiology suites and operating theater, and through direct communication with admitting staff at respective clinical area. To ensure completeness of case ascertainment, an audit coordinator will cross check data entry against hospital admission, discharge records including records of the deceased. For each identified, the site PI and designated research staff will extract relevant data to complete an audit questionnaire and enter the data into a secure web-based Case Report Form, which can only be accessed using a unique hospital identifier and password. All records are anonymized. The following information is being collected. A central audit coordinator checks at weekly interval completeness of questionnaire entry and communicate with site research staff for clarification.

Information extracted included demographics, clinical history (such as admission date, time, clinical areas , referral pattern, past medical history, signs and symptoms at presentation, observations at time of presentation for the clinical episode), laboratory tests, medications, interventions and clinical outcomes

Acute upper gastrointestinal bleeding is defined as the passage of melaena and/or firm clinical evidence and laboratory support for acute blood loss from the upper gastrointestinal (UGI) tract.

This is an observational study. All patients are managed per each center's standard of care. Therefore, no extra intervention is administered and thus there would be no adverse effects expected from the present study. In each enrolled centre, a "lead" consultant together with designated research staff including at least a medical doctor and an audit coordinator will make sure all data are collected correctly and faithfully. The lead investigator of the study will be in direct contact with each centre for any problem related to the study.

This is an observational study. All patients are managed and followed up per each center's standard of care. Therefore, no extra intervention is administered.

Data are presented as percentages with numerator/denominator and as summary statistics of median and inter-quartile ranges (IQR) or mean (standard deviation) as appropriate. Binary regression methods are used to calculate risk ratios and 95% confidence intervals to assess the association of clinical factors with outcomes (inpatient mortality, re-bleeding, red blood cell transfusion). Risk ratios for the type of admission, co-morbidities, and alcohol abuse were computed after adjusting for patient age, which was categorized into quintiles.

At each center a "lead" consultant is designated to represent the hospital on the project. Lead PI and designated research staff identify cases by screening admission records to accident and emergency department and the admission wards, records in the endoscopy centre, interventional radiology suites and operating theater, and through direct communication with admitting staff at respective clinical area. To ensure completeness of case ascertainment, an audit coordinator will cross check data entry against hospital admission, discharge records including records of the deceased. For each identified, the site PI and designated research staff will extract relevant data to complete an audit questionnaire and enter the data into a secure web-based Case Report Form, which can only be accessed using a unique hospital identifier and password. All records are anonymized. The following information is being collected. A central audit coordinator checks at weekly interval completeness of questionnaire entry and communicate with site research staff for clarification.

Information extracted included demographics, clinical history (such as admission date, time, clinical areas , referral pattern, past medical history, signs and symptoms at presentation, observations at time of presentation for the clinical episode), laboratory tests, medications, interventions and clinical outcomes

Acute upper gastrointestinal bleeding is defined as the passage of melaena and/or firm clinical evidence and laboratory support for acute blood loss from the upper gastrointestinal (UGI) tract.

This is an observational study. All patients are managed per each center's standard of care. Therefore, no extra intervention is administered and thus there would be no adverse effects expected from the present study. In each enrolled centre, a "lead" consultant together with designated research staff including at least a medical doctor and an audit coordinator will make sure all data are collected correctly and faithfully. The lead investigator of the study will be in direct contact with each centre for any problem related to the study.

This is an observational study. All patients are managed and followed up per each center's standard of care. Therefore, no extra intervention is administered.

Data are presented as percentages with numerator/denominator and as summary statistics of median and inter-quartile ranges (IQR) or mean (standard deviation) as appropriate. Binary regression methods are used to calculate risk ratios and 95% confidence intervals to assess the association of clinical factors with outcomes (inpatient mortality, re-bleeding, red blood cell transfusion). Risk ratios for the type of admission, co-morbidities, and alcohol abuse were computed after adjusting for patient age, which was categorized into quintiles.

For each included case, the audit coordinator will extract relevant data to complete the audit questionnaires and enter the data into a secure web-based Case Report Form, which can only be accessed using a unique hospital identifier and password. Data will be electronically exported from the website into SPSS. Any duplicate cases will be identified and removed from the dataset prior to analysis. Dates (e.g., date of admission, date of endoscopy, date of discharge) will be verified, and free-text comments regarding presentation and diagnoses were reclassified where possible. Clinical leads will be contacted for clarification when necessary.

Inclusion Criteria:

• Patients would be included in the study if they are aged 18 years or older and have clinical evidence of AUGIB on admission, or clinical evidence of AUGIB while as an inpatient for any other reason. We also include patients with hematochezia as some patients with brisk AUGIB can present rectal bleeding

Exclusion Criteria:

• Patients younger than 18 years old.
• Patients presenting with iron deficiency anemia.

40 hospitals receiving emergency admissions in the Guangdong-Hong Kong-Macao area in China are invited to participate in this study. Unselected acute UGIB adult patients (≥18 years old) admitted within a 2-month period in the second quarter of 2025. These patients are newly admitted patients from both the emergency department and clinics with overt signs of AUGIB, as well as patients who develop bleeding while hospitalized for other reasons.