Introduction: Studies have shown that weekend and holiday admissions for patients with acute coronary syndrome (ACS) are associated with higher incidence of in-hospital mortality and major adverse cardiovascular events (MACE). This has been referred to as the “weekend effect.”

Objectives: We aim to determine whether adults with ACS admitted on weekends have an increased risk for adverse outcomes, primarily in-hospital mortality.

Methodology: This is a retrospective cohort observational study. An ACS database of a prospectively collected cohort was reviewed. Participants in this database included patients with a diagnosis of ACS who satisfied pre-defined inclusion and exclusion criteria. Clinical characteristics and admission data (weekend/holiday versus regular day admission) of all patients were collected. Outcomes of interest were in-hospital mortality, severe heart failure, and re-infarction.

Analysis: Descriptive analysis was done by obtaining the mean and standard deviation of quantitative variables. Proportions and frequencies were reported for qualitative variables. For quantitative variables, T-test of two independent samples was used to determine if there is a significant difference. For categorical variables, the Z-test was used. Multiple logistic regression was also done to explore the predictors of the weekend effect.

Results: A total of 175 patients were included in this study, 59 were admitted on a weekend/holiday and 116 on a regular day. The duration of symptoms prior to admission were longer among those who were admitted during the weekend (40.86±54.11 hrs vs 11.83±8.40 hrs, p=<0.0001). A weekend hospital admission was found to be an independent predictor of in-hospital mortality.

Conclusion: For patients with ACS, a weekend admission was associated with increased in-hospital mortality despite similar management approach in both groups. There is a need to further explore the factors that contribute to this “weekend effect” in our setting by a prospective trial.

Keywords: acute coronary syndrome, weekend effect  

1. Cram P, Hillis SL, Barnett M, Rosenthal GE. Effects of weekend admission and hospital teaching status on in-hospital mortality. Am J Med 2004; 117: 151-7.
2. Al-Lawati, Jawad A., et al. Weekend Versus Weekday, Morning Versus Evening Admission in Relationship to Mortality in Acute Coronary Syndrome Patients in 6 Middle Eastern Countries: Re-sults from Gulf Race 2 Registry. The Open Cardiovascular Medicine Journal, 2012; 6: 106-112
3. Jneid H, Fonarow GC, Cannon CP, et al. Impact of time of presentation on the care and outcomes of acute myo-cardial infarction. Circulation 2008; 117: 2502-9.
4. Bell CM, Redelmeier DA. Mortality among patients admitted to hospitals on weekends as compared with week-days. N Engl J Med 2001; 345: 663-8.
5. Becker DJ. Do hospitals provide lower quality care on weekends? Health Serv Res 2007; 42: 1589-612.
6. Laupland KB, Shahpori R, Kirkpatrick AW, Stelfox HT. Hospital mortality among adults admitted to and discharged from intensive care on weekends and evenings. J Crit Care 2008; 23: 317-24.
7. Kostis WJ, Demissie K, Marcella SW, Shao YH, Wilson AC, Moreyra AE. Weekend versus weekday admission and mortality from myocardial infarction. N Engl J Med 2007; 356: 1099-109.
8. Berger A, Stauffer JC, Radovanovic D, Urban P, Bertel O, Erne P. Comparison of in-hospital mortality for acute myocardial infarction in Switzerland with admission during routine duty hours versus admission during out of hours (insight into the AMIS plus registry). Am J Cardiol 2008; 101: 422-7.
9. Cubeddu RJ, Cruz-Gonzalez I, Kiernan TJ, et al. ST-elevation myocardial infarction mortality in a major academic center “on-” versus “off-” hours. J Invasive Cardiol 2009; 21: 518-23.
10. Aherrera J, Chiong L, Reganit P, Punzalan F. Association of the neutrophil–lymphocyte ratio (NLR) with outcomes in patients admitted for an acute coronary syndrome: a prospective cohort. Philippine Journal of Cardiology 2014; 42(1).
11. Cannon CP, Battler A, Brindis RG, et al. American College of Cardiology key data elements and definitions for measuring the clinical management and outcomes of patients with acute coronary syndromes: a report of the American College of Cardiology Task Force on Clinical Data Standards (Acute Coronary Syndromes Writing Committee). J Am Coll Cardiol 2001;38:2114-30.
12. Alcover JD, Valones AD, Punzalan FER, and Reyes E. The UP-Philippine General Hospital Acute Coronary Events at the Emergency Room Registry (UP PGH-ACER). Acta Medica Philippina 2014; 48 (2): 18-28.
13. Turin TC, Kita Y, Rumana N, et al. Incidence, admission and case-fatality of acute myocardial infarction: weekend versus weekday in a Japanese population: 16-year results from Takashima AMI Regis-try (1988-2003). Eur J Epidemiol 2009; 24: 93-100. s
14. Antman E and J Loscalzo. ST-Segment Elevation Myocardial Infarction. In: Longo D, et al. Harrison’s Principles of Internal Medicine 18th ed. McGraw-Hill Companies, Inc. 2012.
15. Horwich TB, Hernandez AF, Liang L, Albert NM, Labresh KA, Yancy CW, Fonarow GC. Get With Guidelines Steering Committee and Hospitals. Weekend hospital admission and discharge for heart failure: association with quality of care and clinical outcomes. Am Heart J. 2009;158:451–458