ED Mortality & Winter Pressures: A national retrospective cohort study characterising seasonal variation in emergency care use and the association between delays in admission and inpatient mortality.

DC0079

Patients are currently experiencing record waiting times to be seen by medical staff in A&Es in England and even longer waits to be admitted to hospital beds. In 2023/24, only 72% of patients were seen within four hours of arrival and 10% of patients waited more than 12 hours for admission.

There is conflicting evidence about whether increased need for hospital treatment during winter months causes increased waits to be seen and more hospital admissions. There is also conflicting evidence about whether delays in patients being admitted to hospital from the emergency department leads to patients dying due to delayed treatment.

We aim to:

• Find out whether hospitals experience increased demand for emergency care during winter months and what effect this has on A&E waiting times and delays in admissions to hospital.
• Assess whether delays in patients being admitted from the A&E to hospital causes deaths.
• We will use anonymised health care data collected for all hospitals in England to compare A&E attendances, emergency hospital admissions, how unwell patients are, and what treatments they receive during winter and summer months. We use the same data to measure whether the length of time patients wait in the emergency department to be admitted to a hospital ward is related to their risk of dying.
• Our study will help the NHS understand whether it needs to provide extra services such as “surge capacity” for inpatient beds during winter months and, if it does, quantify how much extra capacity is needed to meet increased demand. Our study will also measure how much harm is being caused to patients by delays in patients being admitted to hospital from the emergency department.

4 December 2025

In progress

Study findings will be disseminated accessibly to Integrated Care Board-level commissioners and senior managers involved in planning and developing urgent and emergency care services in England. We will also disseminate finding to the Royal College of Emergency Medicine (RCEM).

This will allow commissioners and policy makers to:

1) Better plan urgent and emergency care service in response to winter pressures and help mitigate patient harms associated with additional demand for care in winter months leading to crowding and delays in treatment

2) Understand the level of avoidable harm patients are experiencing as a result of delays in being admitted to hospital. The RCEM has already used evidence from a less robust study to advocate for changes to the urgent and emergency system and we believe this research can be similarly used to drive policy change aimed at addressing avoidable harm from delays within the urgent and emergency care system.

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