How common is multimorbidity?
Page highlights:
In 2022, an estimated 9.7 million Australians of all ages (38%) were living with multimorbidity (2 or more of 72 selected long-term health conditions).
In 2022, multimorbidity was estimated to be more common among:
- older people, affecting 79% of those aged 85 and over compared with 11% of those aged 0–14 years.
- females (39%) compared with males (37%) of all ages.
In 2022, multimorbidity was estimated to be more common among people living in:
- the lowest 20% of socioeconomic areas (43%) compared with those living in the highest 20% of socioeconomic areas (32%).
- Inner regional (46%) and Outer regional (including remote) areas (45%) compared with Major cities (35%).
The proportion of people living with multimorbidity in 2022 was highest among those who had at least one cardiovascular disease (93%), cancer (88%) or an endocrine disorder (such as diabetes) (86%).
About the data
Multimorbidity estimates on this page are from AIHW analysis of the Australian Bureau of Statistics (ABS) 2022 National Health Survey (NHS) (ABS 2023a). Analysis is of 72 selected long-term health conditions self-reported to the survey.
The NHS is a community-based survey and does not include information from people living in residential aged care facilities, hospitals or prisons. This will exclude people likely to experience certain long-term health conditions such as dementia and cardiovascular disease.
Age-standardised rates are used to remove the influence of age when comparing populations with different age structures. Unless otherwise stated, crude rates are reported, and age-standardised rates are used to inform whether comparisons between population groups are statistically significant. Only statistically significant differences are reported.
For more information on the NHS and how statistically significant differences are identified, see Technical notes.
The selected conditions
The selected conditions are a subset of chronic conditions from the Australian Burden of Disease Study (ABDS) condition list (AIHW 2021) that could be reasonably identified in the 2022 NHS. AIHW has used the ABDS condition list as the conditions have been assessed to be of substantial burden to at least one age group or sex, or to be of significant policy interest, although they can vary in terms of severity and impact. For more information on the conditions included in the analysis, see Technical notes.
Comparability with other estimates
Estimates of multimorbidity vary depending on the number of conditions included in analysis and how they are grouped for counting to determine multimorbidity.
Using the 2022 NHS data, the ABS estimate that 22% of Australians (5.6 million people) had 2 or more of 10 selected chronic conditions in 2022 (ABS 2023c). This is lower than the estimated 9.7 million Australians of all ages (38%) with 2 or more of the 72 selected long-term health conditions in 2022 reported here using the same data.
There is substantial overlap in the conditions included in the ABS list of 10 chronic conditions used in previous AIHW reporting and the list of 72 long-term health conditions used in the current analysis. The difference in these estimates is due not only to additional conditions being included but also to how they are grouped for counting.
For example, the ABS list of 10 chronic conditions combines all mental and behavioural conditions and counts them as one condition. In contrast, the list of 72 long-term health conditions counts mental and behavioural conditions such as depression, anxiety and drug and alcohol use disorders individually so that an individual with more than one of these long-term health conditions is determined to have multimorbidity.
The list of 72 long-term health conditions also includes additional conditions more commonly diagnosed among younger people, such as epilepsy and Down syndrome, with the aim of better describing multimorbidity across all ages.
Multimorbidity is common and becomes more common with increasing age
In 2022, an estimated 38% of Australians (9.7 million people) were living with multimorbidity (2 or more of 72 selected long-term health conditions).
This ranged from 11% of people aged 0–14 years to 79% of people aged 85 and over (Figure 3).
Figure 3: Proportion of people with 0, 1 and 2 or more selected long-term health conditions by age group, 2022
This figure shows that not having any of the selected long-term health conditions decreased with age with 72% of people aged 0–14 not living with a long-term health condition compared with 5.8% of those aged 85 and over.
Notes:
- For the list of long-term health conditions included in analysis, see Table 1 in the Technical notes.
- For data and footnotes, see Table MM02 in the Data tables.
For information on the number of Aboriginal and Torres Strait Islander (First Nations) people living with multiple long-term conditions, see Health and wellbeing of First Nations people.
Variation by age and sex
Overall, multimorbidity is more common among females than males.
An estimated 5.0 million females (39%) and 4.6 million males (37%) were living with multimorbidity in 2022.
However, compared with females of the same age, multimorbidity was statistically significantly more common among males aged 0–14 years and 75 and over (Figure 4).
Figure 4: Proportion of people living with multimorbidity by age group and sex, 2022
This figure shows that the proportion living with multimorbidity increased with age for both males and females.
Notes:
- For the list of long-term health conditions included in analysis, see Table 1 in the Technical notes.
- For data and footnotes, see Table MM02 in the Data tables.
In 2022, the proportion of people living with multimorbidity was:
- 1.7 times as high among males aged 0–14 years (14%) compared with females (8.4%) of the same age
- 1.4 times as high among females aged 15–24 (35%) compared with males of the same age (25%)
- 1.2 times as high among females aged 25–44 (36%) compared with males of the same age (30%)
- slightly higher among females (49%) than males (46%) aged 45–64 although not statistically significantly higher
- slightly higher among males (65%) than females (60%) aged 65–74 although not statistically significantly higher
- 1.1 times as high among males aged 75 and over (80%) compared with females of the same age (73%) (Figure 4).
The underlying prevalence of chronic conditions varies by age and sex
Differences in the level of multimorbidity between males and females across age groups reflect differences in the prevalence of some of the most common conditions among males and females at different ages.
For example, among people aged 0–14 years in 2022, some of the most common of the selected long term health conditions tended to be more common among males than females with an estimated:
- 10% of males and 6.3% of females living with asthma
- 7.0% of males and 3.4% of females living with attention deficit hyperactivity disorder (ADHD).
In contrast, among those aged 15–24 and 25–44 the most common conditions tended to be more common among females than males. For example, among those aged 15–24 in 2022 an estimated:
- 37% of females and 19% of males were living with anxiety
- 22% of females and 11% of males were living with depression
- 13% of females and 8.2% of males were living with asthma.
Anxiety was significantly more common among females aged 25–44 (28%) compared with males (17%) of the same age.
The higher prevalence of deafness and hearing loss among males aged 75 and over (50%) compared with females of the same age (35%) will have contributed to the higher proportion of males with multimorbidity in the age group.
For full results see Data table MM03.
Timing of onset of different conditions and disease trajectory
Different conditions are more likely to develop or be diagnosed at different ages and this can differ by sex. How a condition progresses can also differ by sex.
For example, before puberty, asthma is more common and more severe among males than females. However, this is reversed after puberty when asthma becomes more common among females. It is considered that changes in male and female sex hormones during puberty drive the later onset of asthma among females and may provide protection against the inflammatory processes that cause asthma in males (Jenkins et al. 2022).
Further information and considerations
It is important to note that the 2022 ABS NHS is a community-based survey and does not include information from people living in residential aged care facilities, hospitals or prisons. This will exclude some people likely to experience certain long-term health conditions such, as dementia which is more common among females than males in older age groups. For more information on the scope of the NHS, see Technical notes.
Variation between areas
The prevalence of multimorbidity varies across socioeconomic and remoteness areas.
Multimorbidity becomes more common with increasing socioeconomic disadvantage (Figure 5). In 2022, the estimated prevalence of multimorbidity was:
- 43% among people living in the lowest 20% of socioeconomic areas (the areas of most disadvantage)
- 32% among people living in the highest 20% of socioeconomic areas (the areas of least disadvantage).
By remoteness area, the prevalence of multimorbidity was higher in Inner regional (46%) and Outer regional (including remote) areas (45%) than in Major cities (35%) (Figure 5). For more information on the health of these population groups, see Rural and remote health.
Socioeconomic areas
The population living in the 20% of areas with the greatest overall level of disadvantage are described as living in the ‘lowest socioeconomic areas’. The population living in the 20% of areas with the lowest overall level of disadvantage are described as living in the ‘highest socioeconomic areas’.
For more information, see Technical notes.
Remoteness areas
Remoteness areas divide Australia into 5 classes of remoteness based on a measure of relative access to services. The 5 remoteness areas are Major cities, Inner regional, Outer regional, Remote and Very remote.
Very remote areas are not included in this analysis, as these areas are outside of the scope of the NHS.
For more information, see Technical notes.
Figure 5: Proportion of people with 0, 1 and 2 or more selected long-term health conditions by socioeconomic and remoteness areas, 2022
This figure shows 42% of people living in areas of least disadvantage and 38% in areas of most disadvantage did not report living with a long-term health condition.
Notes:
- For the list of long-term health conditions included in analysis, see Table 1 in the Technical notes.
- Remoteness is classified according to the Australian Statistical Geography Standard (ASGS) 2021 Remoteness Areas structure based on area of residence.
- Socioeconomic areas are measured using the Socio-Economic Indexes for Areas 2021 Index of Relative Socio-Economic Disadvantage (IRSD) based on area of residence. A lower quintile (e.g. the first quintile) indicates relatively greater disadvantage in general. A higher quintile (e.g. the fifth quintile) indicates a relative lack of disadvantage in general.
- For data and footnotes, see Table MM04 in the Data tables.
Variation by condition group
In 2022, the estimated proportion of people living with multimorbidity was highest among people living with at least one cardiovascular condition, cancer or endocrine disorder (such as diabetes) (Figure 6).
Individuals with conditions in these groups tended to be older than those with conditions in other groups. Of people with at least one condition in these groups, the estimated level of multimorbidity in 2022 was:
- 93% among people with a cardiovascular disease (mean age 67 years)
- 88% among people with cancer (mean age 65 years)
- 86% among people with an endocrine disorder (such as type 2 diabetes) (mean age 63 years) (Figure 6).
However, higher average age is not the only factor associated with high levels of multimorbidity. For example, the estimated proportion of people with multimorbidity was:
- 84% among people with a neurological condition (mean age 47 years)
- 82% among people with a mental and behavioural conditions (mean age 40 years) (Figure 6).
Results in this section are of people with a condition in the relevant condition group who also had one or more other conditions, either from within the same condition group (such as heart failure and stroke in the cardiovascular disease group) or from a different condition group.
Age
Although not as common as other conditions people with at least one cardiovascular disease, cancer or endocrine disorders (such as type 2 diabetes) experience relatively high levels of multimorbidity. On average, people with these conditions tend to be older than people with conditions in other conditions groups (Figure 6).
These conditions tend develop later in life due to prolonged exposure to risk factors over time. The higher average age of people with conditions in these groups is likely to be related to the length of time they have had to develop other chronic conditions, prior to developing these conditions.
For more information on risk factors for chronic conditions, see Risk factors.
In contrast, the lower average age of people with a neurological or mental health condition who were living with multimorbidity reflects the relatively younger age at which many of the conditions in those groups are diagnosed including epilepsy and migraine (neurological) and depression and anxiety (mental health).
The high level of multimorbidity among people with conditions in these groups suggests that older age is not the only factor driving high levels of multimorbidity.
Common conditions
How common conditions are will influence multimorbidity with common conditions more likely to co-occur, purely by chance, than rare conditions. For example, deafness or hearing loss and back problems are common conditions and both commonly co-occur.
For more information, see Co-occurring conditions.
Shared risk factors and associations between conditions
Other conditions may have shared risk factors, or one condition may be a risk factor for developing additional conditions. For example, hypertension is a risk factor for both coronary heart disease (CHD) and heart failure. At the same time, CHD is one of the most frequent causes of heart failure (Severino et al. 2020). Among people of all ages with heart failure in 2022, an estimated 43% were living with the effects of CHD based on analysis of self-reported data in the 2022 ABS NHS (Figure 10).
Similarly, research suggest that due a complex interaction between migraine, anxiety and depression, the neurological and mental health conditions may be risk factors for each other (Dresler 2019). Based on analysis of self-reported data in the 2022 ABS NHS, an estimated 2.7% of people of all ages (690,000 people) and 4.0% of females of all ages (514,000 females) were living with both anxiety and migraine (Figures 8 and 9).
For more information on which conditions commonly occur together, see Patterns of multimorbidity.
Further information and considerations
It is important to note that the 2022 ABS NHS is a community-based self-report survey and does not include information from people living in residential aged care facilities, hospitals or prisons. This will exclude some people likely to experience certain long-term health conditions such, as dementia (a neurological condition) or cardiovascular disease, and will influence the estimated prevalence and average age of people with conditions in these groups. For more information on the scope of the NHS, see Technical notes.
Figure 6: Proportion and mean age of people living with multimorbidity by condition group, 2022
This figure shows that multimorbidity was relatively less common among people living with respiratory disease (77%), infant and congenital conditions (76%) and skin disorders (74%).
Notes:
- It is possible for a person to have multiple conditions within a single disease group, such as heart failure and stroke in the cardiovascular disease group. The denominator for each condition group is all people who had at least one condition in the condition group. The numerator includes all people with at least one condition in the condition group who also had another condition in either the same condition group or another group. For the list of long-term health conditions included in analysis, see Table 1 in the Technical notes.
- For data and footnotes, see Table MM05 in the Data tables.
ABS (Australian Bureau of Statistics) (2023a) Microdata: National Health Survey, 2022, AIHW analysis of detailed microdata, accessed 15 February 2025.
ABS (2023b) National Health Survey (2022), ABS website, accessed 3 March 2025.
ABS (2023c) Table 1: Summary health characteristics, 2001 to 2022 (Table 1.3), National Health Survey 2022, ABS website, accessed 3 March 2025.
Dresler T, Caratozzolo S, Guldolf K, Huhn J-I, Loiacono C, Niiberg-Pikksööt T, Puma M, Sforza G, Tobia A, Ornello R and Serafini G (2019) ‘Understanding the nature of psychiatric comorbidity in migraine: a systematic review focused on interactions and treatment implications’. Journal of Headache and Pain, 20, 51, doi:10.1186/s10194-019-0988-x.
Jenkins CR, Boulet L-P, Lavoie KL, Raherison-Semjen C and Singh D (2022) ‘Personalized Treatment of Asthma: The Importance of Sex and Gender Differences’, The Journal of Allergy and Clinical Immunology: In Practice, 10(4): 963-971, doi: 10.1016/j.jaip.2022.02.002.
Severino P, D'Amato A, Pucci M, Infusino F, Birtolo LI, Mariani MV, Lavalle C, Maestrini V, Mancone M and Fedele F (2020) ‘Ischemic Heart Disease and Heart Failure: Role of Coronary Ion Channels’, International Journals of Molecular Sciences Apr 30, 21(9):3167, doi: 10.3390/ijms21093167.