title: Risk and mortality of gastrointestinal hemorrhage in patients with thrombocytopenia: Two nationwide retrospective cohort studies.
abstract: BACKGROUND
  The association between thrombocytopenia (TP) and gastrointestinal hemorrhage was not completely understood. The purpose of this study is to evaluate the risk of gastrointestinal hemorrhage and post-hemorrhage mortality in patients with TP.
  
  
  METHODS
  Using the Taiwan National Health Insurance Research Database, we identified 1033 adults aged ≥18 years diagnosed with TP in 2000-2003. Non-TP cohort consisted of 10,330 adults randomly selected and matched by age and sex from the same dataset. Incident events of gastrointestinal hemorrhage occurring after TP from January 1, 2000, through December 31, 2008, were ascertained from medical claims. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of gastrointestinal hemorrhage associated with TP were calculated. Another nested cohort study consisted of 27,369 patients with hospitalization due to gastrointestinal hemorrhage between January 1, 2004, and December 31, 2010. We calculated the adjusted odds ratios (ORs) and 95% CIs of 30-day mortality after gastrointestinal hemorrhage in patients with and without TP during admission.
  
  
  RESULTS
  The incidences of gastrointestinal hemorrhage for people with and without TP were 14.5 and 5.07 per 1000 person-years, respectively (P<0.0001). Compared to people without TP, patients with TP had increased risk of gastrointestinal hemorrhage (HR, 2.61; 95% CI, 2.05-3.32). In the nested cohort study, TP was associated with post-hemorrhage mortality (OR, 1.98; 95% CI, 1.09-3.59).
  
  
  CONCLUSIONS
  Patients with TP showed higher risks of gastrointestinal hemorrhage and post-hemorrhage mortality. Our findings suggest the urgency of preventing and managing gastrointestinal hemorrhage by a multidisciplinary medical team for this specific population.
authors.affiliation: Department of Anesthesiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.
authors.forename: Po-Han
authors.initials: PH
authors.lastname: Lo
authors.affiliation: Department of Anesthesiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Huang
authors.affiliation: School of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Anesthesiology, Taipei Medical University Hospital, Taipei, Taiwan; Health Policy Research Center, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Chuen-Chau
authors.initials: CC
authors.lastname: Chang
authors.affiliation: Department of Surgery, China Medical University Hospital, Taipei, Taiwan; Department of Surgery, University of IL, Chicago, USA.
authors.forename: Chun-Chieh
authors.initials: CC
authors.lastname: Yeh
authors.affiliation: Division of Pediatric Hematology and Oncology, Department of Pediatrics, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Chia-Yau
authors.initials: CY
authors.lastname: Chang
authors.affiliation: Department of Anesthesiology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan; School of Medicine, Taipei Medical University, Taipei, Taiwan.
authors.forename: Yih-Giun
authors.initials: YG
authors.lastname: Cherng
authors.affiliation: School of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Anesthesiology, Taipei Medical University Hospital, Taipei, Taiwan; Health Policy Research Center, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Ta-Liang
authors.initials: TL
authors.lastname: Chen
authors.affiliation: School of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Anesthesiology, Taipei Medical University Hospital, Taipei, Taiwan; Health Policy Research Center, Taipei Medical University Hospital, Taipei, Taiwan; School of Chinese Medicine, China Medical University, Taichung, Taiwan. Electronic address: ccliao@tmu.edu.tw.
authors.forename: Chien-Chang
authors.initials: CC
authors.lastname: Liao
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D016208:Databases, Factual; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000401:mortality*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D013624:Taiwan / Q000453:epidemiology; D013921:Thrombocytopenia / Q000150:complications*; D055815:Young Adult
keywords: Cohort study; Gastrointestinal hemorrhage; Mortality; Risk; Thrombocytopenia