title: Readmission and mortality in patients discharged with a diagnosis of medical observation and evaluation (Z03*-codes) from an acute admission unit in Denmark: a prospective cohort study.
abstract: We assessed the 30-day risk of readmission and mortality among patients receiving an International Classification of Diseases 10th edition diagnosis of medical observation and evaluation (Z03*) following admission to an acute medical admission unit (AMAU), stratified on any further specification of diagnosis during hospital stay.
  
  
  
  We used Central Denmark's (Midt)-Electronic Patient Journal to identify patients with a Z03*-diagnosis among patients admitted to the AMAU, Aarhus University Hospital Nørrebrogade from April 2012 to March 2013, and noted any specification of diagnosis. Patients were followed from hospital discharge until death, emigration, or completion of 30 days follow-up.
  
  
  
  Of 409 patients with an initial Z03* diagnosis at the AMAU, 55% (n = 226) received a more specific discharge diagnosis after transferral to other departments. Among patients discharged to home with a Z03*-diagnosis, 30% were readmitted within 30 days, while the corresponding figure was 23% for patients receiving a specific diagnosis (p = 0.06). In contrast, corresponding figures for 30-day mortality were 3% for Z03*-diagnosed patients and 10% for those who obtained a specific diagnosis (p = 0.003).
  
  
  
  Patients diagnosed with Z03* at hospital discharge have a substantially lower 30-day mortality, but a higher readmission-rate, compared to patients who obtain a specific diagnosis during the entire hospital stay.
authors.affiliation: Department of Clinical Epidemiology, Institute of Clinical Medicine, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200, Aarhus, Denmark. kare.melchior.hansen@clin.au.dk.|Research Center for Emergency Medicine, Aarhus University Hospital, Aarhus, Denmark. kare.melchior.hansen@clin.au.dk.
authors.forename: Kåre Melchior
authors.initials: KM
authors.lastname: Hansen
authors.affiliation: Department of Clinical Epidemiology, Institute of Clinical Medicine, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200, Aarhus, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Nielsen
authors.affiliation: Department of Clinical Epidemiology, Institute of Clinical Medicine, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200, Aarhus, Denmark.
authors.forename: Betina
authors.initials: B
authors.lastname: Vest-Hansen
authors.affiliation: Research Center for Emergency Medicine, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Anders
authors.initials: A
authors.lastname: Møllekær
authors.affiliation: Department of Clinical Epidemiology, Institute of Clinical Medicine, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200, Aarhus, Denmark.
authors.forename: Reimar Wernich
authors.initials: RW
authors.lastname: Thomsen
authors.affiliation: Acute Medical Admission Unit, Aarhus University Hospital, Nørrebrogade, Aarhus, Denmark.
authors.forename: Ole
authors.initials: O
authors.lastname: Mølgaard
authors.affiliation: Research Center for Emergency Medicine, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Hans
authors.initials: H
authors.lastname: Kirkegaard
authors.affiliation: Department of Clinical Epidemiology, Institute of Clinical Medicine, Aarhus University Hospital, Olof Palmes Allé 43-45, 8200, Aarhus, Denmark.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Svensson
mesh_terms: D000208:Acute Disease / Q000401:mortality*; D000368:Aged; D003718:Denmark / Q000453:epidemiology; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010351:Patient Discharge / Q000706:statistics & numerical data; D010359:Patient Readmission / Q000706:statistics & numerical data*; D011446:Prospective Studies; D057832:Watchful Waiting / Q000706:statistics & numerical data
keywords: Emergency; Epidemiology; Hospital admission; Mortality; Readmission; Z03