title: Increasing incidence of hypotension in the emergency department; a 12 year population-based cohort study.
abstract: BACKGROUND
  The epidemiology of hypotension as presenting symptom among patients in the Emergency Department (ED) is not clarified. The aim of this study was to describe the incidence, etiology, and overall mortality of hypotensive patients in the ED.
  
  
  METHODS
  Population-based cohort study at an University Hospital ED in Denmark from January 1, 2000, to December 31, 2011. Patients aged ≥18 years living in the hospital catchment area with a first time presentation to the ED with hypotension (systolic blood pressure (SBP) ≤100 mm Hg) were included. Outcomes were annual incidence rates (IRs) per 100,000 person years at risk (pyar) and etiological characteristics by means of the International Classification of Diseases, Tenth Revision (ICD-10), as well as 7-day, 30-day, and 90-day all-cause mortality.
  
  
  RESULTS
  We identified 3,268 of 438,198 (1 %) cases with a mean overall IR of 125/100,000 pyar (95% CI: 121-130). The IR increased 28% during the period (from 113 to 152 cases per 100,000 pyar). Patients ≥65 years had the highest IR compared to age <65 years (rate ratio for men 6.3 (95% CI: 5.6-7.1) and for women 4.2 (95% CI: 3.6-4.9)). The etiology was highly diversified with trauma (17%) and cardiovascular diseases (15%) as the most common. The overall 7-day, 30-day and 90-day mortality rates were 15% (95% CI: 14-16), 22 % (95% CI: 21-24) and 28% (95% CI: 27-30) respectively.
  
  
  CONCLUSIONS
  During 2000-2011 the overall incidence of ED hypotension increased and remained highest among the elderly with a diversified etiology and a 90-day all-cause mortality of 28%.
authors.affiliation: Department of Emergency Medicine, Odense University Hospital, Odense, Denmark. Jon.Gitz.Holler@dadlnet.dk.
authors.forename: Jon G
authors.initials: JG
authors.lastname: Holler
authors.affiliation: Department of Respiratory Medicine, Odense University Hospital, Odense, Denmark. dphenriksen@health.sdu.dk.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Henriksen
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, Odense University Hospital, Odense, Denmark. Soeren.Mikkelsen@rsyd.dk.
authors.forename: Søren
authors.initials: S
authors.lastname: Mikkelsen
authors.affiliation: Department of Infectious Diseases, Odense University Hospital, Odense, Denmark. Court.Pedersen@rsyd.dk.
authors.forename: Court
authors.initials: C
authors.lastname: Pedersen
authors.affiliation: Department of Emergency Medicine, Odense University Hospital, Odense, Denmark. Annmarie.Lassen@rsyd.dk.
authors.forename: Annmarie T
authors.initials: AT
authors.lastname: Lassen
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D004636:Emergency Service, Hospital; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007022:Hypotension / Q000453:epidemiology*; D015994:Incidence; D008297:Male; D008875:Middle Aged