title: One-year medical outcomes and emergency department recidivism after emergency department observation for cocaine-associated chest pain.
abstract: OBJECTIVE
  Chest pain is the most common complaint among cocaine users who present to the emergency department (ED) seeking care, and many hospital resources are applied to stratify cocaine users in regard to future cardiac morbidity and mortality. Little is known about the longitudinal cardiac and noncardiac medical outcomes of cocaine users who have been stratified to an ED observation period after their ED visit. We examine 1-year cardiac outcomes in a low- to intermediate-risk sample of patients with cocaine-associated chest pain in an urban ED, as well as examine ED recidivism at 1 year for cardiac and noncardiac complaints.
  
  
  METHODS
  Prospective consecutive cohort study of patients (18 to 60 years) who presented to an urban Level I ED with cocaine-associated chest pain and were risk stratified to low to intermediate cardiac risk. Exclusion criteria were ECG suggestive of acute myocardial infarction, increased serum cardiac markers, history of acute myocardial infarction or coronary artery bypass graft, hemodynamic instability, or unstable angina. Baseline interviews using validated measures of health functioning and substance use were conducted during chest pain observation unit stay and at 3, 6, and 12 months. ED utilization during the study year was abstracted from the medical chart. Zero-inflated Poisson regression analyses were conducted to predict recurrent ED visits.
  
  
  RESULTS
  Two hundred nineteen participants (73%) were enrolled, 65% returned to the ED post-index visit, and 23% returned for chest pain; of these, 66% had a positive cocaine urine screening result. No patient had an acute myocardial infarction within the 1-year follow-up period. Patients with continued cocaine use were more likely to have a recurrent ED visit (P<.001), but these repeated visits were most often related to musculoskeletal pain (21%) and injury (30%), rather than potential cardiac complaints.
  
  
  CONCLUSIONS
  Patients with cocaine-associated chest pain who have low to intermediate cardiac risk and complete a chest pain observation unit protocol have a less than 1% rate of myocardial infarction in the subsequent 12 months.
authors.affiliation: Department of Emergency Medicine, University of Michigan, Ann Arbor, MI, USA. stroh@umich.edu
authors.forename: Rebecca
authors.initials: R
authors.lastname: Cunningham
authors.forename: Maureen A
authors.initials: MA
authors.lastname: Walton
authors.forename: Jim Edward
authors.initials: JE
authors.lastname: Weber
authors.forename: Samantha
authors.initials: S
authors.lastname: O'Broin
authors.forename: Shanti P
authors.initials: SP
authors.lastname: Tripathi
authors.forename: Ronald F
authors.initials: RF
authors.lastname: Maio
authors.forename: Brenda M
authors.initials: BM
authors.lastname: Booth
mesh_terms: D000293:Adolescent; D000328:Adult; D002637:Chest Pain / Q000139:chemically induced*; D002985:Clinical Protocols; D019970:Cocaine-Related Disorders / Q000150:complications*; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology*; D010043:Outcome and Process Assessment, Health Care; D011446:Prospective Studies; D018570:Risk Assessment; D055815:Young Adult