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Do Weekend Admissions Impact Risk of Hospital-Acquired Conditions?

Posted on 09/29/16


A large study published in the British Medical Journal1 found that patients admitted to the hospital on a weekend had an increased risk of developing a hospital-acquired condition (HAC). The authors included 351 million patients discharged from US hospitals from 2002–2010; 19% were admitted on the weekend.

Analysis of the data found:                                                                      

  • At least one hospital acquired condition in 4.8% of hospital admissions (16.7 million inpatient stays).
  • Falls/trauma were the most common event, accounting for 85% of all hospital acquired conditions.
  • Pressure ulcers and catheter-associated urinary tract infections (CAUTIs) were the next HACs found, to a much lesser extent.
  • HACs occurred more often among patients admitted on weekends (5.7%) than those admitted on weekdays (3.7%).
  • Weekend admission was associated with a 21% increased likelihood of incurring an HAC after adjusting for patient, hospital, and severity of admission characteristics.

In their discussion, the authors note these factors potentially affecting HAC rates:

  • Staff volume (physicians, nurses, and ancillary staff) and level of medical expertise are often lower during weekend shifts.
  • Reduced staffing may result in limited attention to each patient on admission.
  • Medical staff often provide weekend coverage for one another and may be less familiar with acute and  chronic conditions of patients who require hospitalization.
  • There are typically reduced resources allocated towards diagnostic testing and operative intervention on weekends.

There were some limitations to the study, including reliance on insurance billing codes, which may not reflect all of the treated conditions. In addition, people admitted for elective surgery on a Sunday night for elective surgery the next day were included as hospital admissions.

Dr. Kumar Dharmarajan, a researcher at Yale University School of Medicine, noted in an accompanying editorial2 that by using billing codes, the study possibly underestimated the number of CAUTIs and central-line associated bloodstream infections. Dr. Dharmarajan later stated that it is difficult to say how conditions on the weekend might contribute to problems because the study did not note which day of the week patients developed a preventable illness or injury.3

This large study addressed the concern both medical staff and patients may have about being admitted to a hospital on the weekend. The authors offer these suggestions for improvement:

  • Added resources and efforts of healthcare administrators and providers are needed to tackle the potential shortcomings in quality of patient care during susceptible periods.
  • Staffing problems are a universal concern. Further training and implementation of prescribed protocols may help mitigate the “weekend effect.”
  • Improved implementation of protocols for patient care may prevent HACs, especially during times of decreased staffing.
  • Initiation of programs to provide a standard for common practice treatments, whether on weekends or weekdays, may be beneficial.

Do you look at day of admission when investigating hospital-acquired infections (HAIs)? Is your hospital staffed the same on weekends as it is during the week?



  1. Attenello Frank J, Wen Timothy, Cen Steven Y, Ng Alvin, Kim-Tenser May, Sanossian Nerses et al. Incidence of “never events” among weekend admissions versus weekday admissions to US hospitals: national analysis  BMJ  2015; 350:h1460.
  2. Dharmarajan Kumar, Kim Nancy, Krumholz Harlan M. Patients need safer hospitals, every day of the week  BMJ  2015; 350:h1826.
  3. Rapaport L. (Reuters). Patients hospitalized on weekends risk more falls and infections. April 21, 2015.

Topics: Infection Prevention

About the Author

Eileen O'Rourke has been practicing hospital-based Infection Prevention since 1984 and served as a consultant with the ECRI Institute in 2014-2015. Eileen's background also includes experience in Microbiology and a Masters in Public Health. She is certified by CBIC and the American Society of Clinical Pathologists and has been active in the Delaware Valley Chapter of APIC (Association for Professionals in Infection Control and Epidemiology), serving as Education Chair and President. Her special interest is education and she has offered multiple infection prevention inservices, including webinars.