What conditions could we prioritise in the primary care setting to reduce non-COVID-related admissions to hospital?

April 22, 2020

Charitini Stavropoulou1, Victoria J Palmer2, Amanda Burls1, Eukene Ansuategi3, Mª Del Mar Ubeda Carrillo3 and Sarah Purdy4

On behalf of the Oxford COVID-19 Evidence Service Team
Centre for Evidence-Based Medicine, Nuffield Department of Primary Care Health Sciences
University of Oxford

1. School of Health Sciences, City, University of London, UK
2.Melbourne Medical School, The University of Melbourne, Victoria, Australia
3.Donostial University Hospital, Spain
4.Bristol Medical School, University of Bristol, UK

Correspondence c.stavropoulou@city.ac.uk

This rapid review has established that targeted interventions for influenza, COPD, CHF, diabetes, UTI and cellulitis should be identified to support increased management in primary care settings. This could result in keeping people well and reducing preventable hospital admissions where possible.

We suggest that a series of rapid reviews are now conducted to identify those existing, effective interventions for COPD, CHF, diabetes, UTI and cellulitis that could be adapted and implemented rapidly, for primary care


Rational for this review

Hospital demand due to the COVID-19 pandemic is increasing and SARS-COV-2-related hospitalisations create pressure on the healthcare system. Many countries have been preparing for the surge in demand by reducing planned hospital admissions to free up capacity to deal with COVID-19 patients. However, hospitals continue to deal with non-COVID related unplanned admissions, some of which are potentially preventable and avoidable.

If unplanned admissions could safely be reduced through targeted primary and community care activities and services, this would help take pressure off hospital beds and staff, enabling greater focus on COVID-19 patients. In turn, this could help protect patients with chronic and acute conditions from exposure to this novel coronavirus by keeping them out of hospital. It may also provide some reassurance to patients who are not being sent to hospital at this time if it can be shown that their condition can be managed just as safely in the community. Perhaps these strategies will result in lasting practices for when Covid19 transmissions can be curbed.

Question addressed in this rapid review

The Oxford COVID-19 Evidence Service Team collected a number of questions from General Practitioners (GPs) in the UK who, among other things, wanted to know: what population groups/comorbid conditions should we otherwise prioritise/focus on to keep well/reduce non-COVID admissions to hospital? This is a complex question that would require different types of evidence to determine comorbidities that lead to hopsitalisation and the different populations affected. It leads to the natural question, of what interventions are then effective at preventing these admissions. We therefore broke the initial question down into a series of answerable questions that could be addressed sequentially in rapid reviews.

This rapid review addresses the first of these questions: Which conditions most often lead to potentially preventable unplanned hospital admissions that are manageable in primary care?

Approach taken

Conceptually, avoidable hospital admissions can be divided into three main areas: primary prevention (e.g. vaccination); early diagnosis and treatment of new conditions (e.g. diabetes); monitoring, control and prompt treatment if there is a deterioration, of ongoing conditions (e.g. heart failure). There has been ongoing discussion on which unplanned hospital admissions are genuinely preventable. To ensure comparability across studies and countries, in recent years the focus has been, therefore, on ambulatory care sensitive conditions (ACSC) (1), although it is recognised that not all admissions for ACSC are preventable or avoidable. The main ACSCs leading to preventable hospital admissions can be classified as: chronic (chronic obstructive pulmonary disease (COPD), diabetes complications, asthma, hypertension, iron deficiency, congestive heart failure, angina, nutritional deficiencies), acute (ear, nose and throat infections, convulsions and epilepsy, cellulitis, pyelonephritis, gangrene, dental conditions, dehydration and gastroenteritis, pelvic inflammatory disease, perforated/bleeding ulcer) and vaccine related (influenza and pneumonia and other vaccine preventable conditions).

For pragmatic reasons, in this rapid review ACSC are used as a proxy measure of potentially preventable conditions that can be treated in a primary or community care setting.

We searched for the latest evidence regarding ACSC in countries with strong primary care provision and a national health system, namely the English NHS, Australia, New Zealand, Canada, the Netherlands and Spain. The most recent and reliable evidence came from national data on secondary care from England, Australia, New Zealand and Spain and two peer-reviewed studies using Canadian and Dutch data. Language barriers meant we could only review data from studies the team had the capacity to deal with.

During the process of data collection, general practitioner input was gathered from Professor Jon Emery, Professor Lena Sanci, Associate Professor Jo-Anne Manski-Nankervis, Associate Professor John Furler. 

Table 1. Summary of the body of evidence

Volume 4 reports using recent national datasets on ACSC

2 cohort studies

Quality Detailed analysis of national data using hospital episode statistics. Data from England and New Zealand as recent as 2019. Data from Australia and Spain from 2017. Data from Canada from 2011. Data from the Netherlands from 2014.
Applicability The datasets and studies are from systems with strong primary care settings and nationalised health care. However, they are from higher income country settings and Anglophone countries predominate.
Consistency The findings show consistency between the datasets regarding the main unplanned hospital admissions across acute and chronic conditions, and vaccinations.



Key findings

The most reliable data that allowed us to synthesise findings from different countries in a meaningful way came from the English NHS, Australia and Spain. Data from New Zealand referred to those aged 45-64 years old, while the data from the two retrospective studies from Canada and the Netherlands did not include enough detail to allow us analysis comparable to the other three.

Table 2 presents a ranking in terms of burden of ACSC for England, Australia and Spain. The burden of ACSC was calculated considering the number of admissions and the length of stay resulting from each hospitalisation. Some findings from all countries are presented in the following sections. Data for all countries can be found in a supplementary file.

Table 2: Burden of preventable ACSC for England, Australia and Spain

Condition UK Australia Spain
Influenza and pneumonia ***** ***** ***
COPD **** *** ****
CCF ** **** *****
Diabetes *** ** *
UTI * **
Cellulitis *

Note: higher number of * indicates higher burden created by preventable admissions (using total annual admissions and length of stay in hospital).

Country specific findings

The latest data from the NHS in England on preventable hospital admissions (2) in 2019 suggest that:

  • Seven conditions account for three quarters of the total cases of ACSC preventable hospitalization (influenza and pneumonia, COPD, ear, nose and throat infections, convulsions and epilepsy, diabetes complications, cellulitis and asthma), and four of them (influenza and pneumonia, COPD, ear, nose and throat infections, convulsions and epilepsy) for more than half.
  • The highest rate of admissions was due to influenza and pneumonia, which showed an increase from previous years. Influenza and pneumonia have also the second highest rate of length of stay.
  • When it comes to preventable readmissions, COPD is the most common condition (19% of total).
  • The greatest increase in cases since 2014 has been observed for hypertension (80% increase), followed by iron deficiency (anaemia) with 53% increase, influenza and pneumonia 47% increase, and diabetes complications with a 39% increase.

The latest data from Australia (3) on potentially preventable ACSC hospital admissions in 2017 suggest:

  • Nearly 10% of all hospital bed days were for potentially preventable hospitalisations.
  • The highest number of cases of preventable hospitalisation is due to COPD, though when translated into days of hospitalisation, pneumonia and influenza are the top causes.
  • Number of preventable hospital admissions have consistently increased since 2014 to reach 715,336 cases in 2017.
  • The majority of causes of preventable hospitalisation (with the exception of angina, diabetes, urine infections and bleeding ulcer that seem to stabilise) have increased since 2014.
  • The main causes of preventable admission to hospital according to cases include COPD, urinary tract infection, dental conditions, cellulitis and iron deficiency. In terms of total days of hospitalisation, the main causes are pneumonia and influenza, congestive cardiac failure, COPD, urinary tract infections and cellulitis.

In Spain the most recent data come from 2017 (4) and show that:

  • There were regional variations in terms of the main preventable hospital admissions.
  • The main reason for hospitalisation were CHF, COPD and diabetes.

In New Zealand, the most recent data for ACSCs for those aged between 45-64 (5) refer to 2019 and show that:

  • The main conditions include: angina, cellulitis, infarction, gastroenteritis, COPD, pneumonia, kidney/urinary infection, CHF, stroke, epilepsy.
  • Their data vary depending on ethnic background.

In Canada, a recent study (6) revealed that:

  • Patients were mostly hospitalised for angina, CHF and COPD with asthma less common in males and hypertension least common in females.
  • The analysis showed that health behavioural variables had the largest effect sizes including heavy smoking (Male HR 2.65 (95% CI 2.17–3.23); Female HR 3.41 (2.81–4.13)) and being underweight (Male HR 1.98 (1.14–3.43); Female HR 2.78 (1.61–4.81)).

In the Netherlands (7):

  • In 2014, 89.8 hospital admissions for ACSCs per 10 000 insured inhabitants were claimed.
  • The main reasons for hospitalisation were angina, infarction and COPD.

This rapid review has established that targeted interventions for influenza, COPD, CHF, diabetes, UTI and cellulitis across England, Spain and Australia to support primary care management will assist to reduce preventable admissions where possible.

Influenza and pneumonia caused the highest number of preventable cases of ACSC hospitalisation (16% of the total) in the English NHS and resulted in the highest number of total days in hospital in Australia. Healthcare systems face a potential need to re-organise care for 12 to 24 months without a vaccine for Covid-19 being available. One public health measure that most of these countries are currently implementing is to ensure the appropriate uptake of current and future flu vaccinations to reduce avoidable admissions. Vaccine related interventions could see a reduction of over 800,000 hospital admissions in England and could free up 424,068 hospital bed days in Australia per year in a normal flu season.

For COPD, CHF, diabetes, UTI and cellulitis we suggest that a series of rapid reviews are conducted  to identify effective interventions that could be implemented and adapted rapidly (as required) in primary care. Prevention and management in the community setting may support hospitals cope with the excess demand due to COVID-19 and to ensure the safety and wellbeing of patients.

Disclaimer:  the article has not been peer-reviewed; it should not replace individual clinical judgement and the sources cited should be checked. The views expressed in this commentary represent the views of the authors and not necessarily those of the host institution, the NHS, the NIHR, or the Department of Health and Social Care. The views are not a substitute for professional medical advice.

Charitini Stavropoulou is a Senior Lecturer in Health Services Research in the School of Health Sciences at City, University of London, England.
Victoria Palmer is Associate Professor in Mental Health Primary Care in The Department of General Practice, Melbourne Medical School, The University of Melbourne, Australia.
Amanda Burls is a public health physician and Emeritus Professor of Public Health in the School of Health Sciences at City, University of London, England.
Eukene Ansuategi is a hospital librarían in the Donostial University Hospital, Spain.
Mª Del Mar Ubeda Carrillo a hospital librarían in the Donostial University Hospital, Spain.
Sarah Purdy is a general practitioner and Professor of Primary Care in the Centre for Academic Primary Care, Bristol Medical School, University of Bristol, England.

We initially searched Medline, EMBASE, CINAHL, PsycInfo, Google Scholar. Grey literature sources searched: King’s Fund, Health Foundation, The Nuffield Trust, WHO, OECD. Search terms included: a) Risk factor OR predictor OR cause and b) Prevent* OR avoid* OR unplanned OR emergency OR unscheduled OR unanticipated OR unexpected OR Ambulatory Care Sensitive Conditions and c) hospital* OR hospital admissions OR hospital readmissions.

To ensure that we had the most up to date figures, where we could we downloaded the latest data on ACSC from National online datasets.


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