title: Risk of revisits to the emergency department in admitted versus discharged patients with chest pain but without myocardial infarction in relation to high-sensitivity cardiac troponin T levels.
abstract: BACKGROUND
  Recent studies have indicated that it may be safe to discharge chest pain patients with an initial high-sensitivity cardiac troponin T (hs-cTnT) level of <5 ng/L from the emergency department (ED) without further evaluation. We sought to assess the effects of discharge from the ED versus admission to hospital on downstream resource utilisation in low-risk chest pain patients.
  
  
  METHODS
  We included all patients who sought medical attention for chest pain during 2 years at the Karolinska University Hospital and who had no myocardial infarction (MI). Adjusted hazard ratios (HRs) were calculated for revisits to the ED, revisits leading to hospitalisation, coronary angiography, or revascularisation during follow-up for admitted compared with discharged patients.
  
  
  RESULTS
  13,046 patients were included, of whom 7694 (59%) had at least one revisit to the ED during a mean of 516 days' follow-up. Admitted patients with hs-cTnT levels of <5 ng/L were 12% more likely to return to the ED during follow-up (HR 1.12, 95% confidence interval (CI) 1.04 to 1.20), and 24% more likely to return to the ED within 30 days (HR 1.24, CI 1.05 to 1.46) than patients who were discharged. The risk of revisit leading to hospitalisation was almost doubled, and the likelihood of undergoing coronary angiography or revascularisation was three-fold in admitted compared with discharged patients.
  
  
  CONCLUSIONS
  Increased risks of revisit to the ED, hospitalisation, coronary angiography, and revascularisation were observed when patients with chest pain and hs-cTnT levels of <5 ng/L were admitted instead of discharged home.
authors.affiliation: Department of Emergency Medicine, Karolinska University Hospital, Stockholm, Sweden; Department of Internal Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Nadia
authors.initials: N
authors.lastname: Bandstein
authors.affiliation: Unit of Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Rickard
authors.initials: R
authors.lastname: Ljung
authors.affiliation: Department of Emergency Medicine, Karolinska University Hospital, Stockholm, Sweden; Department of Internal Medicine, Karolinska Institutet, Stockholm, Sweden. Electronic address: martin.holzmann@karolinska.se.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Holzmann
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D002637:Chest Pain / Q000097:blood / Q000453:epidemiology / Q000628:therapy*; D017023:Coronary Angiography; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis; D010351:Patient Discharge / Q000639:trends*; D010359:Patient Readmission / Q000639:trends*; D018570:Risk Assessment / Q000379:methods*; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D020107:Troponin T
keywords: Chest pain; Emergency department; High-sensitivity cardiac troponin T; Revascularisation; Revisit