1. Lancet. 2017 Jul 1;390(10089):62-72. doi: 10.1016/S0140-6736(17)30782-1. Epub
2017 May 9.

Mortality risks associated with emergency admissions during weekends and public
holidays: an analysis of electronic health records.

Walker AS(1), Mason A(2), Quan TP(2), Fawcett NJ(3), Watkinson P(4), Llewelyn
M(5), Stoesser N(3), Finney J(2), Davies J(6), Wyllie DH(7), Crook DW(8), Peto
TEA(3).

Author information: 
(1)Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, UK;
Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital,
Oxford, UK. Electronic address: sarah.walker@ndm.ox.ac.uk.
(2)Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, UK;
Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital,
Oxford, UK.
(3)Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, UK;
Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital,
Oxford, UK; Oxford University Hospitals NHS Foundation Trust, John Radcliffe
Hospital, Oxford, UK.
(4)Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, UK; Oxford
University Hospitals NHS Foundation Trust, John Radcliffe Hospital, Oxford, UK;
Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford,
UK.
(5)Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, UK;
Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital,
Oxford, UK; Brighton and Sussex Medical School, University of Sussex, Falmer, UK.
(6)Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, UK;
Department of Computer Science, University of Oxford, Oxford, UK.
(7)Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, UK;
Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital,
Oxford, UK; National Infection Service, Public Health England, Colindale, London,
UK.
(8)Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, UK;
Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital,
Oxford, UK; Oxford University Hospitals NHS Foundation Trust, John Radcliffe
Hospital, Oxford, UK; National Infection Service, Public Health England,
Colindale, London, UK.

Comment in
    Lancet. 2017 Jul 1;390(10089):8-9.

BACKGROUND: Weekend hospital admission is associated with increased mortality,
but the contributions of varying illness severity and admission time to this
weekend effect remain unexplored.
METHODS: We analysed unselected emergency admissions to four Oxford University
National Health Service hospitals in the UK from Jan 1, 2006, to Dec 31, 2014.
The primary outcome was death within 30 days of admission (in or out of
hospital), analysed using Cox models measuring time from admission. The primary
exposure was day of the week of admission. We adjusted for multiple confounders
including demographics, comorbidities, and admission characteristics,
incorporating non-linearity and interactions. Models then considered the effect
of adjusting for 15 common haematology and biochemistry test results or proxies
for hospital workload.
FINDINGS: 257 596 individuals underwent 503 938 emergency admissions. 18 313
(4·7%) patients admitted as weekday energency admissions and 6070 (5·1%) patients
admitted as weekend emergency admissions died within 30 days (p<0·0001). 9347
individuals underwent 9707 emergency admissions on public holidays. 559 (5·8%)
died within 30 days (p<0·0001 vs weekday). 15 routine haematology and
biochemistry test results were highly prognostic for mortality. In 271 465
(53·9%) admissions with complete data, adjustment for test results explained 33% 
(95% CI 21 to 70) of the excess mortality associated with emergency admission on 
Saturdays compared with Wednesdays, 52% (lower 95% CI 34) on Sundays, and 87%
(lower 95% CI 45) on public holidays after adjustment for standard patient
characteristics. Excess mortality was predominantly restricted to admissions
between 1100 h and 1500 h (pinteraction=0·04). No hospital workload measure was
independently associated with mortality (all p values >0·06).
INTERPRETATION: Adjustment for routine test results substantially reduced excess 
mortality associated with emergency admission at weekends and public holidays.
Adjustment for patient-level factors not available in our study might further
reduce the residual excess mortality, particularly as this clustered around
midday at weekends. Hospital workload was not associated with mortality.
Together, these findings suggest that the weekend effect arises from
patient-level differences at admission rather than reduced hospital staffing or
services.
FUNDING: NIHR Oxford Biomedical Research Centre.

Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access
article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights
reserved.

DOI: 10.1016/S0140-6736(17)30782-1 
PMCID: PMC5494289
PMID: 28499548