Mental health
Prevalence and impact of mental illness
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Key points
- Over 2 in 5 (44%, or 8.6 million) Australians aged 16–85 are estimated to have experienced a mental disorder at some time in their life, with 1 in 5 (21%, or 4.2 million) having experienced a mental disorder in the previous 12 months.
- Anxiety disorders (such as Social Phobia) are the most common type of disorder, affecting 1 in 6 (17%, or 3.3 million) Australians, followed by Affective disorders (such as Depressive Episode) (8%), and Substance Use disorders (such as Alcohol Dependence) (3.%).
- Almost 1 in 7 (14%) children and adolescents aged 4–17 years are estimated to have experienced a mental illness in the previous 12 months.
- 5% or 800,000 people are estimated to have a severe mental illness, of which 500,000 people have episodic mental illness and 300,000 have persistent mental illness.
- Mental and substance use disorders were the second largest contributor (24%) of the non-fatal burden of disease in Australia.
Mental health is a key component of overall health and wellbeing (WHO 2021). A mental illness refers to a clinically significant disturbance in an individual's cognition, emotional regulation, or behaviour, usually associated with distress or impairment in important areas of functioning (WHO 2022).
On this page the terms ‘mental illness’ and ‘mental disorder’ are both used to describe a range of mental health and behavioural disorders, which can vary in both severity and duration.
How many Australians have experienced a mental disorder?
Of Australians aged 16–85, an estimated:
- 8.6 million have experienced a mental disorder at some time in their life (44% of the population).
- 4.2 million have experienced a mental disorder in the previous 12 months.
The most common mental illnesses in Australia are Anxiety Disorders, Affective Disorders (such as Depression) and Substance use disorders (ABS 2022a).
Figure 1. Estimated number of Australians aged 16-85 experiencing mental illness by time period and disorder, 2021
Figure showing the number of different mental health disorder by males and females during a lifetime and during a 12 month period. This figures also shows to the number of males and females with high or very high psychological distress by disorder group and by age group.
Notes
- Estimates of Alcohol Dependence and Drug Use Disorders have a relative standard error of 25% to 50% and should be interpreted with caution.
- Refer to National Study of Mental Health and Wellbeing methodology, 2020-21 | Australian Bureau of Statistics (abs.gov.au) for more information.
- Some estimates have a relative standard error greater than 25% and should be interpreted with caution. Refer to National Study of Mental Health and Wellbeing methodology, 2020-21 | Australian Bureau of Statistics (abs.gov.au) for more information.
Source: Australian Bureau of Statistics, National Study of Mental Health and Wellbeing: Summary Results, 2020–21; Tables 1.1, 1.3, 2.1, 2.3, 5.1, 5.3, 14.1, 14.3.
Prevalence
A program of surveys, the National Survey of Mental Health and Wellbeing (NSMHWB), began in Australia in the late 1990s. The role of these surveys is to provide evidence on the prevalence of mental illness in the Australian population, the amount of disability associated with mental illness, and the use of health services by people experiencing mental illness. These surveys have 3 main components – a population-based survey of adults, a service-based survey of people with psychotic disorders, and a population-based survey of children.
The National Study of Mental Health and Wellbeing of adults provides information on the 12-month and lifetime prevalence of mental disorders in the Australian population aged 16–85 years. Preliminary estimates from the first tranche of data from the 2020–21 study show that over 2 in 5 (44%) Australians in this age range experience a mental illness at some time in their life (about 8.6 million people). It also estimates that over 1 in 5 (21%) of the population experienced a mental disorder in the previous 12 months (about 4.2 million people).
Of these;
- Anxiety disorders (such as Social Phobia) were the most common, affecting 1 in 6 (17%) Australians
- Affective disorders (such as Depressive Episode) (8%)
- Substance Use disorders (such as Alcohol Dependence) (3%) (ABS 2022a)
Full data are expected to be released in mid July 2023.
Intergenerational health and mental health study
The Intergenerational health and mental health study commenced in 2021. The latest Mental Health Study will update the estimates of the prevalence of mental illnesses from the 2007 National Survey of Mental Health and Wellbeing. It will provide updated statistics and insights into the impact of mental and behavioural and other chronic conditions on Australians and the use of health services and barriers to accessing them, as well as other health topics. The mental health component, The National Study commenced data collection for the first cohort in December 2020 (ABS 2021). Comprehensive data from the first phase of this study were published July 2022.
National Health Survey 2020–21
Another source of information about the mental health of Australians is the Australian Bureau of Statistics’ (ABS) National Health Survey (NHS) 2020–21, which provides information on a range of health conditions including mental and behavioural disorders. In contrast to the NSMHWB which uses a diagnostic instrument, the NHS estimates are based on self-reported information, and records a survey participant as having a mental or behavioural condition during the collection period only if it was also reported as long-term (had lasted, or was expected to last, a minimum of 6 months). The NHS 2020–21 estimated that 1 in 5 (20%) Australians reported that they had a mental or behavioural condition during the collection period (August 2020 to June 2021) (ABS 2022c).
A national household survey, the Australian Child and Adolescent Survey of Mental Health and Wellbeing, was conducted for the second time in 2013–14 (also referred to as the ‘Young Minds Matter’ survey). The findings highlight the most common and burdensome health condition in children and adolescents are mental illness which have significant adverse impacts on their academic outcomes.
Almost 1 in 7 (14%) children and adolescents aged 4–17 years were assessed as experiencing mental illness in the previous 12 months, which is equivalent to about 591,000 (based on the estimated 2017 population) children and adolescents.
Attention Deficit Hyperactivity Disorder (ADHD) was the most common mental illness (7% of all children and adolescents, or about 315,000 based on the estimated 2017 population) followed by,
- Anxiety disorders (7% or about 293,000)
- Major Depressive disorder (3% or about 119,000)
- Conduct disorder (2% or about 89,000)
Almost one third (30% or 4% of all 4–17 year olds) with a illness experienced 2 or more mental illnesses at some time in the previous 12 months.
Male children and adolescents (16%) were more likely than females (12%) to have experienced mental illness in the previous 12 months. The prevalence of mental illness was slightly higher for older females (13% for 12–17 year olds) than for younger females (11% for 4–11 year olds). However, the prevalence for males did not differ markedly between the younger and older age groups (17% and 16% respectively).
There were a number of significant methodological differences between the Young Minds Matter survey and the first child and adolescent survey conducted in 1998. However, it is possible to compare the prevalence data for 3 mental health illnesses (Major depressive disorder, ADHD and Conduct disorder). Prevalence of Depressive disorder increased from 2% to 3%, ADHD decreased from 10% to 8%, and Conduct disorder decreased from 3% to 2% (Lawrence et al. 2015).
Mental illness includes conditions with low prevalence and severe consequences, including psychotic illnesses and a range of other conditions such as eating disorders and personality disorders (DOH 2010). Psychotic illnesses may be characterised by symptoms including disordered thinking, hallucinations, delusions and disordered behaviour, and include Schizophrenia, Schizoaffective disorder, and Delusional disorder.
Estimates from the 2010 National Psychosis Survey were that 64,000 people in Australia aged 18–64 experienced a psychotic illness and were in contact with public specialised mental health services each year. This equates to 5 cases per 1,000 population. The survey found the most frequently recorded of these disorders was Schizophrenia which accounted for almost half of all diagnoses (47%) (Morgan et al. 2011).
For the first time, the Census of Population and Housing (the Census) conducted in 2021 asked Australians about 10 common long-term health conditions. Over 8 million (about 32%) Australians reported that they had been diagnosed with a long-term health condition, with 2.2 million (about 9%) reporting a Mental health condition (including depression or anxiety) (ABS 2022b).
The ABS recommends that the NSMHWB be used as the main source of prevalence data as it uses diagnostic criteria rather than self-reporting as with the Census. Visit Comparing ABS long-term health conditions data sources for more information.
How many Australians experience psychological distress?
Another insight into the mental health and wellbeing of Australians is provided by measures of psychological distress. Psychological distress can be described as unpleasant feelings or emotions that affect a person’s level of functioning and interfere with the activities of daily living. This distress can result in having negative views of the environment, others and oneself, and manifest as symptoms of mental illness, including anxiety and depression.
How is psychological distress measured?
Psychological distress is commonly measured using the Kessler 10 Psychological Distress Scale (K10) a scale based on questions about negative emotional states experienced in the past 30 days (ABS 2012). Someone experiencing psychological distress will not necessarily be experiencing mental illness, although high scores on the K10 are strongly correlated with the presence of depressive or anxious disorders (Andrews and Slade 2001). As it is relatively straightforward to measure, ‘high’ and ‘very high’ levels of psychological distress are often used as a ‘proxy’ for mental illness.
In additional to mental disorder prevalence, the 2020–21 NSMHWB also measured psychological distress. It found that, among Australians aged 16–85, 15% experienced high or very high levels of psychological distress. Females aged 16–34 were more likely to experience psychological distress than males of this age group (26% compared to 14%) (ABS 2022a). Refer to the data visualisation for more detail.
Psychological distress and COVID-19
In the longitudinal study, COVID-19 Impact Monitoring Survey Program, researchers from the Australian National University found a substantial increase in the levels of psychological distress between February 2017 and April 2020, the equivalent of an increase of 8% to 11% of people reporting a serious mental illness. Increases in psychological distress were seen particularly for young Australian adults, with the proportion of people aged 18–24 experiencing high levels of psychological distress increasing from 14% in 2017 to 22% in April 2020 (Biddle et al. 2020).
Over the course of the pandemic, psychological distress has fluctuated, reaching highs in April 2020, October 2020 and October 2021. As of January 2022, psychological distress remained elevated compared to February 2017 (Biddle and Gray 2022).
Impact of mental illness on population groups
It is recognised that some groups experience higher rates of mental illness and psychological distress than others.
In 2018–19, among the total Indigenous Australian population, an estimated 24% (187,500) reported a mental health or behavioural condition, with a higher rate among females than males (25% compared with 23%, respectively). An estimated 31% reported experiencing high or very high levels of psychological distress in the previous 4 weeks (ABS 2019). More information can be found at Australia’s health 2020 – Indigenous health and wellbeing.
Lesbian, gay, bisexual, transgender, intersex, queer/questioning and asexual Australians report lower health and wellbeing compared to Australians generally. A survey of LGBTIQA+ Australians, the Private Lives survey, has been conducted 3 times since 2005. The most recent survey, undertaken in 2020, attracted about 6,800 participants. Three fifths (61%) report having been diagnosed with depression and almost half (47%) with an anxiety disorder, while over half (57%) report experiencing high or very high levels of psychological distress within the past 4 weeks. Furthermore, only 59% of people who accessed a mainstream medical clinic felt that their sexual orientation was very or extremely respected, and only 38% thought that their gender identity was very or extremely respected (Hill et al. 2020). More information can be found at Private Lives 3.
Adults with disability generally experience higher psychological distress than those without disability. In 2017–18, it was estimated that 32% of adults with disability experienced high or very high psychological distress in the previous week, compared to 8% of the population without disability. People with psychological disability were the most likely to report high or very high psychological distress (76%), followed by people with intellectual disability (60%) (AIHW 2020). More information can be found at People with disability in Australia.
Impact and burden of mental illness
Mental illness affects all Australians either directly or indirectly. Mental illness can vary in severity and be episodic or persistent in nature. An estimated 1 in 5 Australians experience mental illness in any given year, most of which will be mild (15% or an estimated 2.3 million Australians among the 15.3 million Australians) or moderate (7%, or an estimated 1.2 million people). It is estimated that around 5% or 800,000 people have a severe mental illness, of which 500,000 people have episodic mental illness and 300,000 have persistent mental illness (Productivity Commission 2020).
Burden of disease
Mental and substance use disorders, such as Depression, Anxiety and Drug use, are important drivers of disability and morbidity. The most recent Australian Burden of Disease Study (2018) examined the health loss due to disease and injury that is not improved by current treatment, rehabilitative and preventative efforts of the health system and society. For Australia, Mental and substance use disorders were estimated to be responsible for 13% of the total burden of disease in 2015, placing it 4th as a broad disease group after Cancer (18%), Musculoskeletal conditions (13%) and Cardiovascular diseases (14%) (AIHW 2021).
In terms of the non-fatal burden of disease, which is a measure of the number of years of ’healthy’ life lost due to living with a disability, Mental and substance use disorders were the 2nd largest contributor (24%) of the non-fatal burden of disease in Australia, behind Musculoskeletal conditions (25%) (AIHW 2021).
Comorbidity
There is an association between diagnosis of mental illness and a physical disorder, often referred to as a comorbid disorder. From the 2007 NSMHWB of adults, 1 in 8 (12%) of people with a 12-month mental illness also reported a physical condition, with 1 in 20 (5%) reporting 2 or more physical conditions (ABS 2008).
According to the 2010 National Psychosis Survey, people with a psychotic illness also frequently experience poor physical health outcomes and comorbidities. For example, over one-quarter (27%) of survey participants had heart or circulatory conditions and over one-fifth (21%) had diabetes (compared with 16% and 6% respectively in the general population). This prevalence of Diabetes is more than 3 times the rate seen in the general population. Other comorbidities included Epilepsy (7% compared with 1% in the general population) and Severe headaches/migraines (25% compared with 9% in the general population) (Morgan et al. 2011).
Where do I go for more information?
More information on mental health can be found at:
- Australian Burden of Disease Study: impact and causes of illness and death in Australia 2018
- Council of Australian Governments Health Council Fifth National Mental Health and Suicide Prevention Plan
- Mental health reports.
ABS (Australian Bureau of Statistics) (2012) Information paper: Use of the Kessler Psychological Distress Scale in ABS health surveys, Australia, 2007-08ABS cat. no. 4817.0.55, ABS, Canberra, accessed 9 March 2022.
ABS (2019) National Aboriginal and Torres Strait Islander Health Survey, 2018–19. ABS cat. no. 4715.0, ABS, Canberra, accessed 16 March 2022.
ABS (2021) Household Impacts of COVID-19 Survey – March 2021 release. ABS cat. No. 4940.0, ABS, Canberra.
ABS (2022a) National Study of Mental Health and Wellbeing, ABS, accessed 18 August 2022.
ABS (2022b) Health: Census, ABS, accessed 26 July 2022.
ABS (2022c) Health Conditions Prevalence, ABS, accessed 27 July 2022.
AIHW (Australian Institute of Health and Welfare) (2020) People with disability in Australia, AIHW, Canberra, accessed 16 March 2022.
AIHW (2021) Australian Burden of Disease Study: Impact and causes of illness and death in Australia 2018, Cat. no. BOD 29, accessed 9 March 2022.
Andrews G and Slade T (2001) ‘Interpreting scores on the Kessler Psychological Distress Scale (K10)’, Australia and New Zealand Journal of Public Health, 25(6): 494–497.
Biddle N, Edwards B, Gray M and Sollis K (2020) Initial impacts of COVID-19 on mental health in Australia, ANU Centre of Social Research and Methods, Canberra.
Biddle N and Gray M (2022) Tracking wellbeing outcomes during the COVID-19 pandemic (January 2022): Riding the Omicron wave, ANU Centre of Social Research and Methods, Canberra.
DoHA (Department of Health and Ageing) (2010) National mental health report 2010: summary of 15 years of reform in Australia’s mental health services under the National Mental Health Strategy 1993-2008, DoHA, Canberra.
Hill AO, Bourne A, McNair R, Carman M and Lyons A (2020) Private Lives 3: The health and wellbeing of LGBTIQ people in Australia, ARCSHS Monograph Series No. 122, Australian Research Centre in Sex, Health and Society, La Trobe University, Melbourne.
Lawrence D, Hancock K and Kisely S (2013) ‘The gap in life expectancy from preventable physical illness in psychiatric patients in Western Australia: retrospective analysis of population based registers’. British Medical Journal, 346, accessed 9 March 2022.
Morgan VA, Waterreus A, Jablensky A, Mackinnon A, McGrath JJ, Carr V, Bush R, Castle D, Cohen M, Harvey C, Galletly C, Stain HJ, Neil AL, McGorry P, Hocking B, Shah S and Saw S (2011) People living with psychotic illness 2010: the second Australian national survey of psychosis, accessed 8 March 2022.
Productivity Commission (2020) Productivity Commission Inquiry – Mental Health Report no.95, Productivity Commission, Canberra.
WHO (World Health Organization) (2022) Mental disorders, WHO, accessed 3 August 2022.
WHO (2021) Mental health: strengthening our responses, WHO, accessed 3 August 2022.
This section was last updated in March 2023.