Clinical question: What factors contribute to increased mortality in weekend hospital admissions?
Background: The “weekend effect” is a commonly known phenomenon, where patients admitted to the hospital on weekends have higher mortality risk than those admitted on weekdays. However, little is known about the factors contributing to the excess mortality associated with weekend admissions.
Setting: Four Oxford University National Health Service hospitals in the United Kingdom (a district general hospital, a large teaching hospital, a specialist orthopedic hospital, and a major cancer center).
Synopsis: Data from the Infections in Oxfordshire Research Database of 503,938 admissions between Jan. 1, 2006, and Dec. 31, 2014 were analyzed. Thirty-day mortality was 4.7%, 5.1%, and 5.8% for patients admitted during weekdays, weekends, and public holidays, respectively (P less than .0001). Fifteen routine hematology and biochemistry test results were determined to be prognostic of high mortality risk. Adjustment for these routine test results reduced excess mortality associated with emergency admissions on weekends and public holidays. Excess mortality was notable for patients admitted on Saturdays and Sundays between 11:00 a.m. and 3:00 p.m. Hospital staffing and workload were not associated with excess mortality. The study is limited by a lack of additional patient factors such as vital signs and blood gas results that may further explain excess mortality on weekends and public holidays.
Bottom line: Patient factors, including laboratory abnormalities, rather than hospital workload and staffing may be the major contributing factors for the excess mortality seen for emergency admissions on weekends and public holidays.
Citation: Walker AS, Mason A, Quan TP, et al. Mortality risks associated with emergency admissions during weekends and public holidays: An analysis of electronic health records. The Lancet. 2017;390(10089):62-72.
Dr. Xu is assistant professor and hospitalist, Icahn School of Medicine of the Mount Sinai Health System, New York.