title: Factors affecting in-hospital mortality in patients with lower gastrointestinal tract bleeding: a retrospective study using a national database in Japan.
abstract: BACKGROUND
  Bleeding of the lower gastrointestinal tract requires hospitalization and can cause in-hospital death in the most serious cases; however, only a few studies have evaluated in-hospital death from bleeding of the lower gastrointestinal tract. The aim of this study was to investigate the in-hospital mortality of patients with bleeding of the lower gastrointestinal tract and elucidate the factors associated with it using a large-scale database.
  
  
  METHODS
  We analyzed a nationwide database in Japan retrospectively. From the Diagnosis Procedure Combination database, we extracted data on patients who were admitted with visible blood in stool between July 1, 2010 and March 31, 2012. We assessed age, sex, comorbidity, cause of bleeding, type of hospital, medications, body mass index (BMI), and need for blood transfusion and treatments. A multivariable logistic regression model was used to examine factors associated with blood transfusion and in-hospital death.
  
  
  RESULTS
  A total of 30,846 patients were identified. The median age was 74 years, and 52.0% of patients were male. A total of 782 patients died in hospital (2.5%), and 8,060 patients (26.1%) needed blood transfusion. In a multivariate analysis, in-hospital death was significantly associated with being older or male; comorbidities, including congestive heart failure, renal disease, and mild to severe liver disease; the cause of bleeding; a nonacademic hospital; nonsteroidal anti-inflammatory drug use; lower BMI; and requirements for blood transfusion, interventional radiology, and surgery. Most factors were similarly associated with blood transfusion.
  
  
  CONCLUSIONS
  In-hospital mortality was 2.5% and was associated with age, sex, comorbidities, cause of bleeding, type of hospital, nonsteroidal anti-inflammatory drug use, BMI, blood transfusion, and requirements for treatments.
authors.affiliation: Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Niikura
authors.forename: Hideo
authors.initials: H
authors.lastname: Yasunaga
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yamaji
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Horiguchi
authors.forename: Kiyohide
authors.initials: K
authors.lastname: Fushimi
authors.forename: Atsuo
authors.initials: A
authors.lastname: Yamada
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Hirata
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Koike
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects; D001803:Blood Transfusion / Q000706:statistics & numerical data; D015992:Body Mass Index; D016208:Databases, Factual; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality*; D017052:Hospital Mortality; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications*; D007297:Inpatients / Q000706:statistics & numerical data*; D007564:Japan / Q000453:epidemiology; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D017678:Sex Distribution
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal