title: Off-hour admission and outcomes for patients with acute myocardial infarction undergoing percutaneous coronary interventions.
abstract: BACKGROUND
  Prior studies have suggested that patients with acute myocardial infarction (AMI) who are admitted during off-hours (weekends, nights and holidays) have higher mortality when compared with patients admitted during regular hours.
  
  
  METHODS
  We analyzed consecutive patients with AMI (ST-elevation myocardial infarction [STEMI] and non-STEMI) who were treated with percutaneous coronary interventions from January 1998 to June 2010 at an academic medical center. Multivariable logistic regression models were used to estimate the association between off-hour admission and clinical outcomes adjusted for demographic and clinical variables.
  
  
  RESULTS
  There were 3,422 and 2,664 patients with AMI admitted during off-hours and regular hours, respectively. Patients admitted during off-hours were more likely to have STEMI (56% vs 48%, P < .001), have cardiogenic shock at presentation (6% vs 4%, P = .002), and develop shock after presentation (6% vs 5%, P = .004). After multivariable analyses, off-hour admission was not significantly associated with in-hospital mortality (odds ratio [OR] 1.12, 95% CI 0.84-1.49), 30-day mortality (OR 1.12, 0.87-1.45), or 30-day readmissions (OR 1.01, 0.84-1.20) but was significantly associated with composite major complications and any of emergent coronary artery bypass graft surgery, ventricular arrhythmia, stroke/transient ischemic attack, and gastrointestinal/retroperitoneal/intracranial bleeding (OR 1.27, 1.05-1.55, P = .015). There was no significant time trend in the adjusted mortality difference between off-hours and regular hours. The results were not different between STEMI and non-STEMI.
  
  
  CONCLUSIONS
  Patients who were admitted during off-hours did not have higher mortality or readmission rates as compared with ones admitted during regular hours at an academic medical center.
authors.affiliation: Division of Preventive Medicine, Mayo Clinic, Rochester, MN. Electronic address: sorita.atsushi@mayo.edu.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sorita
authors.affiliation: Health Care Policy and Research, and Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Lennon
authors.affiliation: The Knowledge and Evaluation Research Unit and the Center for the Science of Health Care Delivery, Mayo Clinic, Rochester, MN.
authors.forename: Qusay
authors.initials: Q
authors.lastname: Haydour
authors.affiliation: Division of Pulmonary and Critical Care, Mayo Clinic, Rochester, MN.
authors.forename: Adil
authors.initials: A
authors.lastname: Ahmed
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN.
authors.forename: Malcolm R
authors.initials: MR
authors.lastname: Bell
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN.
authors.forename: Charanjit S
authors.initials: CS
authors.lastname: Rihal
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN.
authors.forename: Bernard J
authors.initials: BJ
authors.lastname: Gersh
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN.
authors.forename: Jody L
authors.initials: JL
authors.lastname: Holmen
authors.affiliation: Division of Health Care Policy and Research, Mayo Clinic, Rochester, MN.
authors.forename: Nilay D
authors.initials: ND
authors.lastname: Shah
authors.affiliation: Division of Preventive Medicine, Mayo Clinic, Rochester, MN.
authors.forename: Mohammad Hassan
authors.initials: MH
authors.lastname: Murad
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN.
authors.forename: Henry H
authors.initials: HH
authors.lastname: Ting
mesh_terms: D039602:After-Hours Care; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality* / Q000628:therapy*; D010043:Outcome and Process Assessment, Health Care; D062645:Percutaneous Coronary Intervention; D012770:Shock, Cardiogenic