Hospital care

This page presents information on the number and characteristics of dementia-related episodes of admitted patient care (referred to as ‘hospitalisations’) from the National Hospital Morbidity Database, including hospitalisations due to dementia in 2020–21 by:

Each hospitalisation is assigned a principal diagnosis (the main reason for being admitted to hospital) and can also be assigned 1 or more additional diagnoses (conditions that impact the provision of care but are not the main reason for being admitted to hospital). This page largely focuses on hospitalisations with a principal diagnosis of dementia, or ‘hospitalisations due to dementia’. See Hospitalisations due to dementia versus hospitalisations with dementia for information on hospitalisations with dementia recorded as an additional diagnosis. 

See Box 9.1 for key terms and considerations for hospitalisations for people with dementia and the Technical notes for further information on hospitals data.

Box 9.1: Data considerations for hospitalisations related to dementia

This page aims to provide a comprehensive picture of the impact of dementia on Australia’s hospital systems. Hospitalisations where dementia was recorded as the principal diagnosis provide information on dementia-specific hospitalisations. In contrast, hospitalisations with dementia recorded as an additional diagnosis provide information on episodes of care where dementia impacted the hospitalisation but the reason for needing hospital care was not dementia.

The following terms are used to distinguish dementia hospitalisations:

  • Hospitalisations due to dementia are hospitalisations where dementia was recorded as a principal diagnosis.
  • Hospitalisations with dementia are hospitalisations where dementia was recorded as a principal diagnosis and/or an additional diagnosis.

It is important to note that the statistics presented here cannot be considered a full count of hospitalisations among people with dementia for various reasons including:

  • Hospital records only include conditions that were significant in terms of treatment, investigations needed and resources used during the ‘episode of care’. This means that hospitalisations among people with mild dementia may be under-recorded because the early stages of dementia are less likely to affect the care provided in hospitals.
  • Since 2015 dementia may be recorded in hospitals data using ‘supplementary codes’ rather than as an additional diagnosis (especially when dementia was not strongly impacting the care received by the patient) (see Box 9.3 for more information). Unfortunately, supplementary codes are currently not available in our data.

There is also a possibility that specific dementia types may be misclassified or simply attributed to Unspecified dementia by medical professionals in the hospital setting (Crowther et al. 2017). As a result, the number of hospitalisations for a specific dementia type may not be accurate. The most reliable data are likely to be for the most common types of dementia. Caution should be taken when interpreting hospital statistics by dementia type.

Hospitalisations due to dementia in 2020–21

In 2020–21, there were just over 11.8 million hospitalisations in Australia. Of these, about 25,500 were hospitalisations due to dementia, which is equivalent to 2 out of every 1,000 hospitalisations in Australia.

Table 9.1 shows that of the hospitalisations due to dementia in 2020–21:

  • there were more hospitalisations for men than women (13,100 hospitalisations compared to 12,400 hospitalisations)
  • men also had a higher age-standardised rate of hospitalisations than women (51 hospitalisations for men and 37 hospitalisations for women, per 10,000 people aged 60 and over)
  • the average length of stay was 13 days—this was 5 times higher than the average length of stay of 2.6 days for all hospitalisations
  • the average length of stay was longer for men (13 days) than women (12 days).
Table 9.1: Overview of hospitalisations due to dementia in 2020–21 by sex

 

Men

Women

Persons

Number of hospitalisations

13,100

12,400

25,500

Age-standardised rate (number per 10,000)

51

37

43

Average length of stay, days per hospitalisation

13

12

13

Total number of bed days

175,500

149,500

325,000

Note: Age-standardised rates, which apply to people aged 60 and over, were standardised to the Australian population as at 30 June 2001 and are expressed per 10,000 population.

Source: AIHW analysis of National Hospital Morbidity Database.

With increasing age, hospitalisations due to dementia increased in number but decreased in length

There were distinct patterns in hospitalisations due to dementia in 2020–21 by age and sex (Figure 9.1):

  • the number of hospitalisations for both men and women increased with age up to 80–84 years, then decreased in the oldest ages
  • the rate of hospitalisations increased for both men and women up to age 90–94, before decreasing among those aged 95 and over
  • people with younger onset dementia (aged under 65) had a greater average length of stay (22 days) than older people—the average length of stay decreased with increasing age, to 10 days for people hospitalised due to dementia aged 95 and over. This trend was observed among both men and women.

Figure 9.1: Overview of hospitalisations due to dementia in 2020–21, by age and sex

Figure 9.1 is a bar graph showing the estimated number of hospitalisations due to dementia in Australia by sex and age in 2020–21, as well as sex and age breakdowns for rate of hospitalisations (per 10,000 population) due to dementia, bed days and average length of stay (days). For both men and women, the number of hospitalisations due to dementia peaked in people aged in their eighties but the age-standardised rate of hospitalisations due to dementia was highest among those in their nineties. The age-standardised rate of hospitalisations was higher in men than women across all age groups, with the difference greatest among those aged 90 to 94. The average length of stay for hospitalisations due to dementia decreased with increasing age from 22 days for people aged less than 65 to 10 days for people aged 95 and over.

Hospitalisations due to dementia increased over time

Figure 9.2 shows the number and age-standardised rate of hospitalisations due to dementia between 2011–12 and 2020–21:

  • the rate of hospitalisations increased gradually each year from 2011–12 to 2014–15 (4.2% annual average increase) and from 2015–16 to 2020–21 (1.6% annual average increase)
  • between 2014–15 and 2015–16 there was a large increase in both the number of hospitalisations (24% increase) and the age-standardised rate (22% increase). This increase is likely due to changes in coding for rehabilitation which came into effect in 2015–16 (see Box 9.2 for more information)
  • although the numbers of hospitalisations were similar throughout the period, men consistently had higher rates of hospitalisations than women.

Figure 9.2: Hospitalisations due to dementia between 2009–10 and 2020–21: number and age-standardised rates

Figure 9.2 is two line graphs showing the estimated number and age-standardised rates of hospitalisations due to dementia in Australia by sex between 2011–12 and 2020–21. The number and age-standardised rate of hospitalisations both increased steadily during this period, with a surge observed between 2014–15 and 2015–16, which could be attributed to changes in coding for rehabilitation that came into effect in 2015–16. Men consistently had higher rates of hospitalisations than women.

Box 9.2: Coding changes impacting hospitalisations due to dementia over time

With many national health data collections, the primary purpose is to support the administrative objectives of the collecting organisation rather than to monitor disease. Factors such as changes in coding practices may affect how well conditions are recorded in the data.

The period 2014–15 to 2015–16 saw a substantial increase in hospitalisations due to dementia (where dementia was the principal diagnosis). In July 2015, a new coding standard ACS2104 Rehabilitation was introduced into the ICD-10-AM. Changes that may have led to an increase in admissions with dementia coded as the principal diagnosis include:

  • prior to July 2015, patients who were admitted to hospital specifically for rehabilitation were assigned a principal diagnosis of Z50.9 Care involving use of rehabilitation procedure, unspecified, and the condition which led to the need for rehabilitation (such as dementia) was assigned as an additional diagnosis
  • in July 2015, this coding standard was revised so that the principal diagnosis should be assigned to the condition which led to the need for rehabilitation, and Z50.9 Care involving use of rehabilitation procedure, unspecified should be assigned as an additional diagnosis.

When changes such as these are implemented in short time periods, distinct steps up or down in numbers and rates are expected to be observed in administrative data.

Almost 30% of hospitalisations due to dementia were for Alzheimer’s disease

In 2020–21, the most common dementia types recorded in hospitalisations due to dementia were:

  • Alzheimer’s disease (29%)
  • Other dementia (21%)
  • Unspecified dementia (17%)
  • Vascular dementia (12%) (Figure 9.3).

There were differences by sex in the dementia types recorded in hospitalisations due to dementia. Compared to men, there was a slightly higher proportion of hospitalisations among women due to Alzheimer’s disease (31% of women compared with 28% of men) and Unspecified dementia (19% of women compared with 15% of men). There was a higher proportion of men with hospitalisations due to Vascular dementia than women (14% of men compared with 9% of women).

Although not a distinct type of dementia, delirium superimposed on dementia occurs when a person with pre-existing dementia experiences delirium, and is a common cause of hospitalisations among people with dementia. In 2020–21, 12% of hospitalisations due to dementia were for Delirium superimposed on dementia (Table S9.3).

As a person may have multiple types of dementia, it is possible to have more than one type of dementia recorded among hospitalisations with dementia. While the majority of dementia hospitalisations had only one type of dementia recorded, almost 10% (just over 9,000 hospitalisations) had 2 or more types recorded.

Figure 9.3: Hospitalisations due to dementia in 2020–21: percentage, by type of dementia and sex

Figure 9.3 is a bar graph showing the percentage of hospitalisations due to dementia in Australia by type of dementia and sex in 2020–21. The most common dementia types recorded were Alzheimer’s disease, Other dementia, Unspecified dementia and Vascular dementia. The proportion of hospitalisations due to Alzheimer’s disease and Unspecified dementia was slightly less common among men compared with women, but Vascular dementia was more common among men. Note that Delirium superimposed on dementia was included in the total number of hospitalisations due to dementia but is not shown in this figure as it is not a distinct type of dementia.

How did hospitalisations due to dementia end?

In 2020–21, 39% of all hospitalisations due to dementia ended in the patient being discharged home (Figure 9.4). This proportion was considerably less than seen for all hospitalisations in 2020–21, where 93% ended in the patient being discharged home (AIHW 2021).

Of all dementia hospitalisations, 6.1% of hospitalisations were discharged to their usual place of residence which was a residential aged care facility. An additional 15% were transferred to a residential aged care facility, which was not their usual place of residence. Of those discharged or transferred to a residential aged care facility, 2 in 3 patients were aged over 80 (Table S9.9).

Around 25% of hospitalisations due to dementia ended with a ‘Statistical discharge’, which is when the intent of care changed during their stay in hospital (for example, from acute care to rehabilitation or palliative care). A further 9.2% ended with discharge or transfer to another acute hospital and 4.4% ended with the death of the patient.

Figure 9.4: All hospitalisations and hospitalisations due to dementia in 2020–21: percentage, by mode of separation

Figure 9.4 is a bar graph showing the percentage of all hospitalisations, and hospitalisations due to dementia in Australia by mode of separation in 2020–21. It shows that almost 39% of hospitalisations due to dementia ended in the patient being discharged home. In contrast, 93% of all hospital separations involved a discharge home. Just under 16% of hospitalisations due to dementia ended with patients transferring to residential aged care, with an additional 6% being discharged to a residential aged care facility which was their usual place of residence.

5% of all hospitalisations due to dementia involved palliative and other end-of-life care

In 2020–21, there were over 900 palliative care-related hospitalisations due to dementia, accounting for 5.3% (3.2% palliative care and 2.2% other end-of-life care) of all hospitalisations due to dementia (Figure 9.5a). Palliative care-related hospitalisations include hospitalisations with a care type of palliative care, in which specialist palliative care is provided (referred to as palliative care) as well as hospitalisations where a palliative care diagnosis was recorded, but care was not necessarily delivered by a palliative care specialist (referred to as other end-of-life care). See Palliative care services in Australia for more detail.

Compared to women, men tended to have higher rates of hospitalisations due to dementia involving palliative care or other end-of-life care, and this held across most age groups; for both men and women, the rate of hospitalisations increased with age (Figure 9.5b).

Figure 9.5: Palliative care and other end-of-life care hospitalisations due to dementia in 2020–21, by age and sex: (a) number and (b) age-specific rate

Figure 9.5 is two bar graphs showing the estimated number and age-specific rates of palliative care and other end-of-life care hospitalisations due to dementia in Australia by sex and age in 2020–21. Men generally had higher rates of hospitalisations due to dementia involving palliative care or other end-of-life care than women across most age groups. There was generally an increasing trend in the rate of hospitalisations with age for both men and women.

How do hospitalisations due to dementia vary by geographic and socioeconomic areas?

Figure 9.6 shows the age-standardised rate of hospitalisations due to dementia by state and territory, remoteness areas and socioeconomic groups for 2020–21.

In 2020–21, after adjusting for population differences, the age-standardised rate of hospitalisations due to dementia for people aged 60 and over:

  • varied across states and territories—ranging from 35 hospitalisations per 10,000 population in Tasmania to 58 hospitalisations per 10,000 population in the Northern Territory
  • varied by remoteness— the rate of hospitalisations due to dementia was highest in Major cities (46 hospitalisations per 10,000 population) and lowest in Remote areas (35 hospitalisations per 10,000 population)
  • was lowest among people living in the highest socioeconomic area compared to all other socioeconomic areas, which had similar rates of hospitalisation (ranging between 44 and 47 hospitalisations per 10,000 population).

Socioeconomic and demographic factors such as income, education, employment, geographic access to health and social support services, as well as belonging to a culturally and linguistically diverse (CALD) community, may impact hospitalisations with dementia. These and other barriers may affect this group's ease of access to hospital services. Refer to Understanding Dementia among Indigenous Australians and Dementia in priority groups for more information.

Figure 9.6: Hospitalisations due to dementia in 2020–21: age-standardised rate, by state and territory, remoteness area and socioeconomic area

Figure 9.6 is a bar graph showing the age-standardised rates of hospitalisations due to dementia by state or territory, remoteness areas and socioeconomic areas in 2020–21. After adjusting for population differences, the rates varied by state or territory as well as by remoteness areas, with the highest rates in the Northern Territory and Major cities, and the lowest rates in Tasmania and Remote areas. Rates of hospitalisations due to dementia were lowest in the highest socioeconomic area and fairly similar across all other socioeconomic areas.

Hospitalisations due to dementia versus hospitalisations with dementia

Previous sections have presented hospitalisations due to dementia (that is, when dementia was recorded as the principal diagnosis), but understanding hospitalisations with dementia (that is all hospitalisations with a record of dementia, whether as the principal and/or an additional diagnosis) provides important insights on the wide-ranging conditions that can lead people living with dementia to use hospital services.

In 2020–21, there were just over 93,600 hospitalisations with dementia (46,300 men and 47,300 women), which is equivalent to 8 out of every 1,000 hospitalisations in Australia (AIHW 2022).

Trends over time in hospitalisations with dementia were different to trends in hospitalisations due to dementia (Figure 9.7). The age-standardised rate of hospitalisations with dementia were fairly stable between 2011–12 and 2014–15 (0.2% annual average increase) and decreased slightly between 2015–16 and 2019–20 (2.5% annual average decrease). Between 2014–15 and 2015–16, there was a decrease in both the number (8.1% decrease) and the age-standardised rate (10.6% decrease) of hospitalisations. By comparison, the age-standardised rate of hospitalisations due to dementia increased between 2014–15 and 2015–16 (as shown in the Hospitalisations due to dementia increased over time section).

Refer to Box 9.3 for more information on how changes to the way dementia has been recorded in hospital data over this period may have contributed to the decrease in hospitalisations with dementia.

Figure 9.7: Hospitalisations with dementia between 2009–10 and 2020–21 by sex: (a) number and (b) age-standardised rate

Figure 9.7 is two line graphs showing the estimated number and age-standardised rates of hospitalisations with dementia in Australia by sex between 2011–12 and 2020–21. The age-standardised rate of hospitalisations with dementia were fairly steady between 2011–12 and 2014–15, and decreased slightly between 2015–16 and 2020–21.

Box 9.3: Potential factors impacting hospitalisations with dementia over time

In July 2015, 29 supplementary codes for chronic conditions (including dementia) and a new Australian Coding Standard were implemented in existing classification systems and coding rules for assigning specific codes to diagnoses found in medical records (ACCD 2015). As a result, from July 2015 onwards dementia can be recorded in hospital data using a supplementary code when it does not meet the criteria to be recorded as a principal or additional diagnosis.

It is not yet understood whether the introduction of supplementary codes has impacted recording of chronic conditions as additional diagnoses in hospitals data. It may have resulted in less recording of dementia as an additional diagnosis, especially in cases where dementia did not directly impact the care provided to the patient. Data on supplementary codes were not available for analysis in this report. The exclusion of supplementary codes may explain the sudden decrease in the rate of hospitalisations with dementia between 2014–15 and 2015–16, and subsequently, the slightly declining rates to 2020–21 (Figure 9.7).

The quality of the supplementary codes data is currently being assessed and a decision will be made in due course regarding whether or not these data will be made available for analysis and reporting purposes.

What were the most common principal diagnoses when dementia was an additional diagnosis?

In 2020–21 there were almost 77,200 hospitalisations where dementia was recorded as an additional diagnosis. Examining the most common principal diagnoses recorded for these hospitalisations provides insights on the diverse reasons why people with dementia require hospital services. The most common principal diagnoses were:

  • Delirium, not induced by alcohol and other psychoactive substances, ICD-10-AM codes F05.0–9 (7,000 hospitalisations or 9% of hospitalisations where dementia was an additional diagnosis)
  • Problems related to medical facilities and other health care, ICD-10-AM codes Z75.0–9 (6,500 hospitalisations or 8.4% of hospitalisations where dementia was an additional diagnosis).
    • these hospitalisations are where patients are required to stay in hospital longer to rehabilitate or are waiting to transfer to new accommodation. These hospitalisations may be counted as a separate hospitalisation rather than a continuation of a hospitalisation from an acute episode (such as a fracture)
  • Fracture of the femur, ICD-10-AM codes S72.0–9 (4,900 hospitalisations or 6.3%)
  • Other disorders of urinary system, ICD-10-AM code N39X (3,100 hospitalisations or 4.1%) (Figure 9.8).

Other common principal diagnoses recorded for these hospitalisations included respiratory diseases, cardiovascular diseases and sepsis.

Falls (ICD-10-AM codes W00–W19) accounted for nearly 97% of all hospitalisations due to fractures of the femur, and 95% of hospitalisations due to fractures of the lumbar spine and pelvis, where dementia was an additional diagnosis. Women had twice as many hospitalisations than men for a fracture of the femur and fracture of the lumbar spine and pelvis, with an additional diagnosis of dementia (Table S9.10).

Figure 9.8: Most common principal diagnoses where dementia was an additional diagnosis in 2020–21, by sex

Figure 9.8 is a bar graph showing the number of hospitalisations for the most common principal diagnoses when dementia was recorded as an additional diagnosis, by sex in 2020–21. The most common principal diagnoses were Delirium, not induced by alcohol and other psychoactive substances, Problems related to medical facilities and other healthcare, and Fracture of femur.