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Off-hour presentation and outcomes in patients with acute myocardial infarction: systematic review and meta-analysis

BMJ 2014; 348 doi: (Published 21 January 2014) Cite this as: BMJ 2014;348:f7393
  1. Atsushi Sorita, senior fellow in preventive medicine and public health1,
  2. Adil Ahmed, senior research fellow2,
  3. Stephanie R Starr, consultant physician3,
  4. Kristine M Thompson, consultant physician4,
  5. Darcy A Reed, consultant physician5,
  6. Larry Prokop, reference librarian6,
  7. Nilay D Shah, senior associate consultant7,
  8. M Hassan Murad, consultant physician1,
  9. Henry H Ting, consultant physician8
  1. 1Division of Preventive Medicine, Mayo Clinic, Rochester, MN, USA
  2. 2Division of Pulmonary and Critical Care, Mayo Clinic, Rochester, MN, USA
  3. 3Division of Community Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN, USA
  4. 4Department of Emergency Medicine, Mayo Clinic, Jacksonville, FL, USA
  5. 5Division of Primary Care Internal Medicine, Mayo Clinic, Rochester, MN, USA
  6. 6Mayo Clinic Libraries, Mayo Clinic, Rochester, MN, USA
  7. 7Division of Health Care Policy and Research, Mayo Clinic, Rochester, MN, USA
  8. 8Division of Cardiovascular Diseases, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
  1. Correspondence to: H H Ting Ting.Henry{at}
  • Accepted 28 November 2013


Objective To assess the association between off-hour (weekends and nights) presentation, door to balloon times, and mortality in patients with acute myocardial infarction.

Data sources Medline in-process and other non-indexed citations, Medline, Embase, Cochrane Database of Systematic Reviews, and Scopus through April 2013.

Study selection Any study that evaluated the association between time of presentation to a healthcare facility and mortality or door to balloon times among patients with acute myocardial infarction was included.

Data extraction Studies’ characteristics and outcomes data were extracted. Quality of studies was assessed with the Newcastle-Ottawa scale. A random effect meta-analysis model was applied. Heterogeneity was assessed using the Q statistic and I2.

Results 48 studies with fair quality, enrolling 1 896 859 patients, were included in the meta-analysis. 36 studies reported mortality outcomes for 1 892 424 patients with acute myocardial infarction, and 30 studies reported door to balloon times for 70 534 patients with ST elevation myocardial infarction (STEMI). Off-hour presentation for patients with acute myocardial infarction was associated with higher short term mortality (odds ratio 1.06, 95% confidence interval 1.04 to 1.09). Patients with STEMI presenting during off-hours were less likely to receive percutaneous coronary intervention within 90 minutes (odds ratio 0.40, 0.35 to 0.45) and had longer door to balloon time by 14.8 (95% confidence interval 10.7 to 19.0) minutes. A diagnosis of STEMI and countries outside North America were associated with larger increase in mortality during off-hours. Differences in mortality between off-hours and regular hours have increased in recent years. Analyses were associated with statistical heterogeneity.

Conclusion This systematic review suggests that patients with acute myocardial infarction presenting during off-hours have higher mortality, and patients with STEMI have longer door to balloon times. Clinical performance measures may need to account for differences arising from time of presentation to a healthcare facility.


  • Contributors: AS designed the study; collected, analyzed, and interpreted the data; and drafted and revised the paper. AA designed the study, collected and analyzed the data, and drafted and revised the paper. SRS, KMT, and DAR collected and analyzed the data and revised the paper. LP collected the data and revised the paper. NDS conceptualized and designed the study, interpreted the data, and revised the paper. MHM conceptualized and designed the study, analyzed and interpreted the data, and drafted and revised the paper. HHT conceptualized and designed the study, oversaw and managed the progress, planned analysis and interpreted the data, and drafted and revised the paper. All authors had full access to all of the data in the study and can take responsibility for the integrity of the data and the accuracy of the data analysis. AS is the guarantor.

  • Funding: Mayo Clinic Division of Cardiovascular Diseases, Mayo Clinic Quality Academy, Mayo Clinic College of Medicine, and Mayo Clinic Center for Science of Healthcare Delivery. Researchers were independent from funders and sponsors, and the study sponsor did not have any influence on the study design; the collection, analysis, and interpretation of data; the writing of the article; or the decision to submit it for publication.

  • Competing interests: All authors have completed the ICMJE uniform disclosure form at and declare: no support from any organization for the submitted work other than those listed above; no financial relationships with any organizations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.

  • Ethical approval: The study did not require an ethics committee approval.

  • Transparency: The lead author (the manuscript’s guarantor) affirms that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.

  • Data sharing: The dataset is available from the corresponding author at Ting.Henry{at}

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