title: Survival after splanchnic vein thrombosis: A 20-year nationwide cohort study.
abstract: BACKGROUND
  Splanchnic vein thrombosis (SVT) is a rare condition with a poorly understood prognosis.
  
  
  METHODS
  We conducted a population-based cohort study (1994-2013), using data from Danish nationwide medical registries, to examine the short- and long-term prognosis of SVT. We identified 1915 incident cases of SVT and a matched comparison cohort of 18,267 persons without SVT (matched by cancer, cirrhosis, pancreatitis, alcohol-related disease, atrial fibrillation/flutter, venous thromboembolism, heart failure, and inflammatory bowel disease). We used the Kaplan-Meier method to calculate absolute risk of death. Using stratified Cox regression, we computed mortality rate ratios (MRRs) with 95% confidence intervals (CIs), comparing SVT patients with the comparison cohort.
  
  
  RESULTS
  We identified 1,500 (78%) patients with portal vein thrombosis, 204 (11%) with hepatic vein thrombosis, and 211 (11%) with mesenteric vein thrombosis. The mortality risks were markedly higher for SVT patients than for the comparison cohort during the first 5years of follow-up (30-day risk: 20.6% vs. 0.7%; 31-364-day risk: 21.7% vs. 4.7%; and 1-5-year risk: 25.4% vs. 17.7%). The corresponding MRRs were 40.7 (95% CI: 32.4-51.1), 7.4 (95% CI: 6.4-8.6), and 2.4 (95% CI: 2.1-2.8), respectively. The 30-day mortality was higher after mesenteric vein thrombosis than portal and hepatic vein thrombosis, whereas portal vein thrombosis had a stronger impact on mortality after 30days than hepatic and mesenteric vein thrombosis.
  
  
  CONCLUSIONS
  Splanchnic vein thrombosis has a poor short- and long-term prognosis that varies according to subtype of thrombosis. Reasons for the increased mortality in patients with SVT need further clarification.
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark. Electronic address: kks@clin.au.dk.
authors.forename: Kirstine Kobberøe
authors.initials: KK
authors.lastname: Søgaard
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Bianka
authors.initials: B
authors.lastname: Darvalics
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Erzsébet
authors.initials: E
authors.lastname: Horváth-Puhó
authors.affiliation: Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Henrik Toft
authors.initials: HT
authors.lastname: Sørensen
mesh_terms: D000328:Adult; D000368:Aged; D006502:Budd-Chiari Syndrome / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology / Q000401:mortality; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000473:pathology; D011379:Prognosis; D016016:Proportional Hazards Models; D013152:Splanchnic Circulation; D016019:Survival Analysis; D020246:Venous Thrombosis / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality
keywords: Budd-Chiari syndrome; Epidemiology; Mesenteric venous thrombosis; Portal vein thrombosis; Prognosis