title: Death or revascularization among nonadmitted ED patients with low-positive vs negative troponin T results.
abstract: OBJECTIVE
  Compare outcomes among emergency department (ED) patients with low-positive (0.01-0.02 ng/mL) vs negative troponin T.
  
  
  METHODS
  Retrospective cohort study of nonadmitted ED patients with troponin testing at a tertiary-care hospital. Trained research assistants used a structured tool to review charts from all nonadmitted ED patients with troponin testing, 12/1/2009 to 11/30/2010. Outcomes of death and coronary revascularization were assessed at 30 days and 6 months via medical record review, Social Security Death Index searches, and patient contact.
  
  
  RESULTS
  There were 57596 ED visits; with 33388 (58%) discharged immediately, 6410 (11%) assigned to the observation unit, and 17798 (31%) admitted or other. Troponin was measured in 2684 (6.7%) of the nonadmitted cases. Troponin was negative in 2523 (94.0%), low positive in 78 (2.9%), and positive (≥0.03 ng/mL) in 83 (3.1%). Of troponin-negative cases, 0.8% (95% CI, 0.4-1.1%) died or were revascularized by 30 days, vs 2.8% (95% CI, 0.0-6.7%) of low-positive cases (risk difference [RD], 2.0%; 95% CI, -1.8 to 5.9%). At 6 months, the rates were 1.7% (95% CI, 1.1-2.2%) and 12.9% (95% CI, 5.0-20.7%) (RD, 11%; 95% CI, 3.3-19.1%). Death alone at 30 days occurred in 0.4% (95% CI, 0.1-0.6%) vs 1.3% (95% CI, 0.0-3.8%) (RD, 0.9%; 95% CI, -1.6 to 3.4%). Death at 6 months occurred in 1.2% (95% CI, 0.8-1.6%) vs 11.7% (95% CI, 4.5-18.9%) (RD, 10%; 95% CI, 3.3-17.7%).
  
  
  CONCLUSIONS
  Among patients not initially admitted, rates of death and coronary revascularization differed insignificantly at 30 days but significantly at 6 months. Detailed inspection of our results reveals that the bulk of the added risk at 6 months was due to non-cardiac mortality.
authors: Department of Emergency Medicine, Brigham and Women's Hospital, Boston, MA; Harvard Medical School. Electronic address: cbaugh@partners.org.
authors: Christopher W
authors: CW
authors: Baugh
authors: Department of Emergency Medicine, Brigham and Women's Hospital, Boston, MA; Harvard Medical School.
authors: Joshua M
authors: JM
authors: Kosowsky
authors: Department of Cardiology, Brigham and Women's Hospital, Boston, MA; Harvard Medical School.
authors: David A
authors: DA
authors: Morrow
authors: Department of Emergency Medicine, Brigham and Women's Hospital, Boston, MA; Harvard-Affiliated Emergency Medicine Residency.
authors: Jonathan D
authors: JD
authors: Sonis
authors: New York Institute of Technology College of Osteopathic Medicine, New York, NY.
authors: Allen G
authors: AG
authors: Gold
authors: Department of Emergency Medicine, Brigham and Women's Hospital, Boston, MA.
authors: Clare E
authors: CE
authors: Ronan
authors: Department of Emergency Medicine, Brigham and Women's Hospital, Boston, MA; Harvard Medical School.
authors: Daniel J
authors: DJ
authors: Pallin
mesh_terms: D000368:Aged; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006331:Heart Diseases / Q000097:blood / Q000401:mortality / Q000601:surgery; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D063868:Patient Outcome Assessment; D062645:Percutaneous Coronary Intervention / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D013997:Time Factors; D020107:Troponin T / Q000097:blood*
chemical_list: D020107:Troponin T