Health Spotlight: Mental illness

Mental illness has previously been defined by the Council of Australian Governments as ‘a clinically diagnosable disorder that significantly interferes with a person’s cognitive, emotional or social abilities’. It can include a range of mental health problems such as anxiety, depression, substance use disorders and psychotic disorders.³

Anxiety has recently been the most common type of mental disorder, with 17% of Australians experiencing anxiety disorders in 2020-21. This type of mental illness includes generalised anxiety disorder, which involves excessive anxiety over everyday events, and specific phobias like agoraphobia (fear of going outside) and claustrophobia (fear of confined spaces).⁵

Other common disorders included affective mood disorders such as depression and bipolar, which impacted 8% of the population in 2020-21, and substance use disorders, affecting 3% of Australians over the same time period.³

Different mental illnesses will cause different symptoms in sufferers. For anxiety disorders, common symptoms include panic attacks, chronic fears or anxious thoughts that interfere with a person’s day to day life, and physical stress symptoms such as trembling, sweating and feeling faint.⁵

For mood disorders like depression, symptoms can include persistent feelings of sadness and negative thoughts, and an inability to enjoy one’s usual activities.

To diagnose mental illness, your doctor or mental health professional will often ask questions about your mood, your behaviour and any recent traumatic experiences you have had.

There are often a range of factors and causes that contribute to someone suffering a mental illness. These can range from genetics – if your family has a history of certain mental illnesses – and negative early childhood experiences, to recent trauma and stress in your adult life.⁶

Certain groups of people are also more at risk for mental illness than others. For instance, First Nations people are more than three times as likely to suffer psychological distress than the general population, and LGBTQI+ people suffer depression four times as often as other Australians, and anxiety two and a half times as often.

In addition, young people are particularly at risk for mental illness, with over 75% of mental health problems occurring before the age of 25.⁴

^{1 Mental health. Australian Bureau of Statistics, July 2022}

^{2 National Study of Mental Health and Wellbeing. Australian Bureau of Statistics, July 2022}

^{3 Mental health: Prevalence and impact. Australian Institute of Health and Welfare, November 2022}

^{4 Beyond Blue Statistics 2022}

^{5 Anxiety disorders. Victorian Department of Health, October 2022}

^{6 Mental illness. Healthdirect.gov.au, March 2023}