Depression describes a group of illnesses characterized by excessive or long term depressed mood which affects the person's life. The most severe form of clinical depression is called a depressive episode, which can come on without apparent cause, although in some cases a distressing event might trigger the condition.

The person becomes low-spirited, loses enjoyment of life and suffers disturbed sleep patterns. During a depressive episode the person can lose their appetite, lack concentration and energy and may lose weight. Feelings of guilt are also common.
Sometimes feelings of hopelessness and despair can lead to thoughts of suicide.

Click here for more information on depression

Bipolar mood disorder is the new name for what was called manic depressive illness. The new name better describes the extreme mood swings: from depression and sadness to elation and excitement. People with bipolar mood disorder experience recurrent episodes of depressed and elated moods.

When a person is in a manic state they may exhibit some of the following symptoms: elevated mood; increased energy and over activity; reduced need for sleep; irritability; rapid thinking and speech; lack of inhibitions; grandiose plans and beliefs; and lack of insight.

Many people with bipolar mood disorder experience depressive episodes. The depression usually occurs without an obvious cause. The person loses interest and pleasure in activities enjoyed before. They may withdraw and stop seeing friends, avoid social activities and cease simple tasks such as showering and shopping. They are overwhelmed by a deep sadness, lose their appetite, cannot concentrate and may experience associated feelings of guilt or hopelessness. Some attempt suicide as life becomes meaningless or they feel too guilty to go on.

Click here for more information on Bipolar Mood Disorder

Schizophrenia interferes with the mental functioning of a person and, in the long term, may cause changes to a person's personality. The onset of the illness may be rapid, with acute symptoms developing over several weeks, or it may be slow, developing over months or even years. During onset, the person often withdraws from others, gets depressed and anxious and develops extreme fears or obsessions.

The major symptoms of schizophrenia include delusions, hallucinations and thought disorder. Other symptoms include loss of drive, blunted expression of emotions, social withdrawal, lack of insight or awareness of other conditions and thinking difficulties.

Click here for more information on Schizophrenia

Anxiety disorders are a group of illnesses characterized by persistent feelings of high anxiety. There are feelings of continual or extreme discomfort and tension, with the fear of panic attacks, usually without discernible cause. People are likely to be diagnosed with an anxiety disorder with their level of anxiety and feelings of panic are so extreme that they significantly interfere with daily life and stop them doing what they want to do. Anxiety disorders affect the way the person thinks, feels and behaves and, if not treated, cause considerable suffering and distress.

2007 National Survey of Mental Health and Wellbeing found that:

• Almost half the total population (45.5%) experience a mental health disorder at some point in the lifetime.
• One if five, or 20% of the Australian population aged 16-85 years, experienced mental disorders in the previous 12 months [of their survey]. This is equivalent to 3.2 million Australians.
• One in 16 (6.2%) had affective (mood) disorders; one in seven (14.4%) had anxiety disorders; and one in 20 (5.1%) had substance use disorders.
• Based on these prevalence rates, it is estimated that nearly 1 million Australians have affective disorders; over 2.3 million had anxiety disorders and over 800,000 had substance use disorders in the previous 12 months.
• The prevalence of mental disorders declines with age: from 1 in 4 young people (16-24) to 1 in 20 (75-85 years)
• Only one third of people (34.9%) with a mental health disorder used health services for their mental health problem – and two thirds of people with a mental health disorder did not report using services for their mental health disorder.

Depression and anxiety are the most prevalent mental disorders experienced by Australians. Depression alone is predicted to be one of the world’s largest health problems by 2020.1

Around one million Australian adults and 100,000 young people live with depression each year. On average, one in five people will experience depression in their lives; one in four females and one in six males.2m

Among young Australians aged 12-25 years, depression is the most common mental health problem. Around one in ten young Australians will experience an anxiety disorder in any given 12 month period.3 At least one third of young people have had an episode of mental illness by the age of 25 years.4

Mental disorders and suicide account for 14.2 % of Australia’s total health burden – which equates to 374,541 years of healthy life lost (DALYs).5

Estimates suggest that up to 75 % of people presenting with alcohol and drug problems also have additional mental health problems.6

Reports indicate that up to 85% of homeless people have a mental illness.