Primary and community health care—for example, care from a general practitioner or community health nurse—can effectively manage and treat many health conditions. Primary care provides an opportunity for early intervention, helping reduce the risk of a person developing a disease, their symptoms worsening, or complications developing.

If this care is not available or not accessed, a person can end up requiring hospital care that could potentially have been avoided. A specific set of these hospital admissions are known as ‘potentially preventable hospitalisations’.

Why measure potentially preventable hospitalisations?

Potentially preventable hospitalisations (PPH) are often used as a proxy measure of the effectiveness of health care in the community, as higher rates may suggest a lack of timely, accessible and adequate primary care.

However, there are many other reasons why an area or group of people may have higher rates of PPH—including higher rates of disease, lifestyle factors and other risks, as well as a genuine need for hospital services. Some PPH may not be avoidable, such as those for patients with complex illness, or patients having procedures as follow-up to primary care.

This means that it is important not to assume that higher rates of PPH always indicate a less effective primary care system. Rather, PPH are a useful tool for identifying and investigating variation between different groups of people to better understand health inequalities. PPH can help guide research about how different groups access health services, including possible barriers they may face and areas of unmet demand.

What this report adds

The Australian Institute of Health and Welfare (AIHW) has reported PPH annually since 2004. For the first time, this report and the accompanying data and interactive graphs examine how rates of PPH have varied over time depending on where a person lives and their circumstances—including how old they are, whether they are male or female, Aboriginal and/or Torres Strait Islander, live in a lower socioeconomic area, or live in a more remote part of Australia.

The report also illustrates how changes to hospital coding standards and clinical practices, and differences in admission policies can artificially affect rates of PPH for some conditions, and aims to assist users of PPH to better interpret the data.

Potentially preventable hospitalisations are grouped into 3 broad categories:

  • Vaccine-preventable conditions: hospitalisations due to diseases that can be prevented by vaccination, such as influenza, measles and whooping cough.
  • Acute conditions: these conditions usually have a quick onset and may not be preventable, but theoretically would not result in hospitalisation if timely and adequate care was received in the community. This category includes conditions such as dental conditions, urinary tract infections and ear, nose and throat (ENT) infections.
  • Chronic conditions: these long-lasting conditions may be preventable through lifestyle change, but can also be managed in the community to prevent worsening of symptoms and hospitalisation. This category includes conditions such as diabetes complications, chronic obstructive pulmonary disease (COPD) and asthma.

How common are potentially preventable hospitalisations?

In 2017–18, 748,000 admissions in public and private hospitals were classified as PPH, accounting for 1 in 15 hospital admissions (6.6%) and 1 in 10 hospital bed days (9.8%).

Overall, the most common reason for hospitalisation was COPD, but Pneumonia and influenza (vaccine-preventable) and Congestive cardiac failure accounted for the most days of hospital care, reflecting their tendency to affect elderly people who often require more complex or longer-term hospital care.

The most common cause of PPH in males was COPD; in females it was urinary tract infections

Males and females had similar rates of PPH overall in 2017–18, but males had higher rates of PPH for COPD, Congestive cardiac failure, type 2 Diabetes complications, Cellulitis and Epilepsy, while females had higher rates of PPH for Urinary tract infections (UTIs), Iron deficiency anaemia, Asthma and Hypertension.

The recent increase in PPH rates was driven by hospitalisations for influenza

In 2017–18, Pneumonia and influenza (vaccine-preventable) accounted for 1 in 13 PPH admissions (7.6%) and 1 in 7 PPH bed days (14%).

PPH rates for Pneumonia and influenza (vaccine-preventable) were highest in people aged 65 and over and children under 5, and in Indigenous Australians of all ages, highlighting the importance of vaccination in these groups.

Nearly half of all PPH were in older people, mostly due to chronic conditions

In 2017–18, 46% of all PPH were for people aged 65 and over. Of these PPH, the majority (61%) were for Chronic conditions, most commonly COPD, Congestive cardiac failure, Iron deficiency anaemia and type 2 Diabetes complications. The most common Acute conditions PPH were UTIs and Cellulitis.

There is continuing debate about the ‘preventability’ of hospital admissions in older people, due to the complexity of disease that is often seen in these age groups.

Children had PPH for infections, dental conditions and asthma

In 2017–18, three-quarters (77%) of PPH in children aged 0–14 were for Acute conditions such as Ear, nose and throat infections and Dental conditions. Children also had PPH for Chronic conditions including Asthma, type 1 Diabetes complications, and in Indigenous children, Rheumatic heart disease.

Childhood vaccination coverage in Australia is high, and PPH rates for Other vaccine-preventable conditions (excluding hepatitis B) remained low between 2012–13 and 2017–18.

Indigenous Australians had high rates of PPH, and rates have increased faster in females

In 2017–18, there were nearly 45,000 PPH for Aboriginal and/or Torres Strait Islander (subsequently referred to as Indigenous) Australians, at a rate 3 times as high as Other Australians. Disparities in age-standardised rates of PPH between Indigenous Australians and Other Australians were observed for most conditions, particularly COPD, Cellulitis, Diabetes complications, Rheumatic heart disease and Pelvic inflammatory disease.

Between 2012–13 and 2017–18, the rate of Total PPH for Indigenous Australians increased by 25%, compared with a 15% increase for Other Australians.

Over the 6 years, Total PPH rates increased by 32% for Indigenous females and 16% for Indigenous males. The most striking difference was the rapid increase in PPH for COPD in Indigenous women (38%), compared to a 13% increase in Indigenous men.

The ‘health gap’ may have widened for people living in remote areas and areas of socioeconomic disadvantage

PPH rates are often shown to increase with increasing remoteness and socioeconomic disadvantage.

The gap in PPH rates between people living in the lowest and highest socioeconomic areas increased for a number of PPH conditions from 2012–13 to 2017–18, particularly for common Chronic conditions such as COPD and Diabetes complications, and Acute conditions such as ENT infections, Cellulitis and Gangrene.

Similarly, between 2012–13 and 2017–18, the gap in PPH rates between people living in Very remote areas and Major cities widened for some conditions, particularly COPD, Gangrene and Pelvic inflammatory disease.

Improving the PPH indicator

This report examines certain factors outside the primary health care system that have had an impact on PPH rates, such as changes in hospital coding standards and clinical practices, and differences in admission policies. Conditions known to be affected include hepatitis B, Iron deficiency anaemia, Angina and some conditions requiring rehabilitation care, and these factors could be considered in future revisions of the PPH indicator.

In the future, the use of linked data sets could allow investigation of the relationships between PPH and disease prevalence, use of primary health care, use of medicines and health outcomes.