Each year, 6% of adults in England will experience an episode of depression and more than 15% of people will experience an episode of depression over the course of their lifetime. For many people the episode will not be severe, but for more than 20% the depression will be more severe and have a significant impact on their daily lives. Recurrence rates are high: there is a 50% chance of recurrence after a first episode, rising to 70% and 90% after a second or third episode, respectively.

Women are between 1.5 and 2.5 times more likely to be diagnosed with depression than men. However, although men are less likely to be diagnosed with depression, they are more likely to die by suicide, have higher levels of substance misuse and are less likely to seek help than women.

The symptoms of depression can be disabling and the effects of the illness pervasive. Depression can have a major detrimental effect on a person's personal, social and work life. This places a heavy burden on the person and their carers and dependents, as well as placing considerable demands on the healthcare system.

Depression is the leading cause of suicide, accounting for two-thirds of all deaths by suicide.

Under-treatment of depression is widespread, because many people are unwilling to seek help for depression and detection of depression by professionals is variable. For example, of the 130 people with depression per 1,000 population, only 80 will consult their GP. Of these 80 people, 49 are not recognised as having depression. This is mainly because they have contacted their GP because of a somatic symptom and do not consider themselves as having a mental health problem (despite the presence of symptoms of depression).

  • National Institute for Health and Care Excellence (NICE)