60 second Factfile: Depression
Continuous low mood, low self-esteem, suicidal thoughts, unexplained aches and pains, lack of motivation, avoidance of social contact.
Living with depression
The symptoms and severity of depression vary from person to person; some people may go through a short period of mild depression, while for others it can become a way of life for many years. It is often compared to grieving, but with notable differences: it is very difficult for people with depression to look forward to the future, and depression can occur simultaneously with anxiety disorder, panic disorder or mania (bipolar disorder).
Depression is caused by a combination of biological, psychological and social factors. Often, it is one particular event that can trigger it, although it can develop gradually and may not present until years after the event. Treatment must therefore be similarly varied; the most common is a combination of antidepressants and talking therapies. Antidepressants increase the levels of neurotransmitters in the brain, which in turn help to improve mood and emotion. This then gives the patient the boost needed to work through the psychological causes. All patients respond to treatment differently - antidepressants are known to improve mood in about 50-65 per cent of patients - but over 80 per cent of cases are curable.
Depression is not simply "feeling sad". Clinical depression is a serious, recognised medical illness; studies show that people struggling with the condition have decreased activity in certain parts of the brain and increased levels of stress hormones.