Major depressive disorder
Major depressive disorder (MDD) – simply known as depression – is a mental health condition involving prolonged (i.e. lasting more than two weeks) and intense feelings of sadness or misery – at times without any apparent reason.
Our findings
The mood episodes attributed to MDD tend to cause significant personal distress and impair one’s work, social or daily functioning. Other forms of depression, such as persistent depressive disorder, peri-partum depression or premenstrual dysphoric disorder, also exist.
Key findings
2.1 million Australians suffered from depression in 2015
1 in 5 women will experience MDD
1 in 8 men will experience MDD
Prevalence
Between 2014 and 2015, the Australian Bureau of Statistics estimated that 2.1 million Australians (9.3 per cent of our population) were suffering from some form of depression. On average, around one in six people (one in five women and one in eight men) will experience MDD at some point in their lives.
Problems with anxiety at the same time are also common, for instance involving panic disorder, social anxiety disorder (SAD) or generalised anxiety disorder (GAD).
Some individuals also turn to alcohol or other substances to cope with their depression or anxiety, and it can be difficult to discern the cause and effect of these conditions. Worryingly, roughly only a third will seek help.
Possible causes
It is normal to feel sad or low at times, but when these mood episodes become persistent or severe, a diagnosis of MDD may be given. Often, this is triggered by a significant life stressor (e.g. job loss or death of a loved one).
Research has shown certain chemical imbalances in the brain, involving serotonin or noradrenaline, may play a role in the disorder. Depression may run in families with some people carrying a higher genetic risk. Living with a chronic physical or mental illness also puts one at a greater risk for developing MDD.
Symptoms
There are a constellation of associated symptoms, so one person with MDD may present quite differently from someone else. These include:
- feeling sad or down most of the time
- losing interest or pleasure in formerly enjoyable activities
- difficulties with sleep
- sleeping excessively
- fatigue or loss of energy
- feeling worthless or guilty
- feeling restless
- significant changes in appetite or weight
- being indecisive or unable to concentrate
- recurring thoughts of dying or hurting oneself
Treatment options
Effective treatments for MDD exist involving antidepressant medications coupled with psychological interventions, such as cognitive behavioural therapy (CBT), interpersonal therapy (IPT) or mindfulness-based approaches. Social support and lifestyle changes may be helpful as well.
Contact the Centre for Mental Health and Brain Sciences
We work with academia, industry and government to form meaningful and impactful partnerships. For more information, please email cmhbs@swinburne.edu.au.