title: Differences between acute myocardial infarction and unstable angina: a longitudinal cohort study reporting findings from the Register of Information and Knowledge about Swedish Heart Intensive Care Admissions (RIKS-HIA).
abstract: OBJECTIVE
  The aim of this study was to compare risk factors and comorbidities in patients with a first episode of acute coronary syndrome (ACS), being either acute myocardial infarction (AMI) or unstable angina pectoris (UAP).
  
  
  METHODS
  Cross-sectional and prospective.
  
  
  METHODS
  The Swedish population.
  
  
  METHODS
  A total of 145 346 consecutive patients aged 25-105 years included in the Swedish Register of Cardiac Intensive Care Admission (Register of Information and Knowledge about Swedish Heart Intensive Care) and admitted to hospital between 1 January 1996 and 30 June 2009 with a first episode of either AMI or UAP.
  
  
  METHODS
  Type of ACS and 1-year outcome.
  
  
  RESULTS
  Compared with patients with UAP, AMI patients were more likely to be older; men; and former or current smokers; they were also more likely to have had diabetes and peripheral artery disease, but had lower rates of prior heart failure (HF) and fewer cardioprotective medications on admission. Among patients aged <65 years, 1.4% of men and 1.6% of women with UAP died within 1 year in 2003-2006 compared with 4.2% of men and 3.1% of women AMI patients (multiple-adjusted OR 3.54 (99% CI 2.29 to 5.48) in women and 2.65 (99% CI 2.11 to 3.34) in men). Corresponding proportions in patients aged ≥65 years was 7.5% in men and 7.6% in women with UAP and 21.5% in men and 17.8% in women with AMI.
  
  
  CONCLUSIONS
  In patients with a first-time ACS episode, male sex, slightly older age, smoking, diabetes and peripheral arterial disease (PAD), but fewer cardioprotective medications, were major determinants for presenting with AMI. Despite increasingly active treatment in AMI and more inclusive diagnostic criteria in recent years, persistently worse prognosis was observed in AMI patients.
authors.affiliation: Institute of Health and Care Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg,  Sweden.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Dudas
authors.forename: Lena
authors.initials: L
authors.lastname: Björck
authors.forename: Tomas
authors.initials: T
authors.lastname: Jernberg
authors.forename: Georgios
authors.initials: G
authors.lastname: Lappas
authors.forename: Lars
authors.initials: L
authors.lastname: Wallentin
authors.forename: Annika
authors.initials: A
authors.lastname: Rosengren