personnes en dépression
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Mental health, an essential component of health, is a state of well-being, an ability of the mind to function normally and respond appropriately to environmental stimuli. Mental disorders occur when this state of well-being is disrupted by specific conditions such as depression. The individual is then unable to adapt to difficult or even painful situations and maintain his or her mental equilibrium.


Is depression a mental illness?

The term “depression” is a bit overused, we often say “I’m depressed”, but this illness represents a real public health issue. Depression is the most common psychiatric disorder and it is estimated that one person in 10 will be affected in their lifetime, with a ratio of 2 women to 1 man.


Depression in figures

Depression is the most common psychiatric disorder, with around 5-15% of the French population experiencing a depressive episode at some point in their lives. It occurs at all stages of life.

Today, it is estimated that 3% of children aged between 3 and 17 are affected by this illness. The prevalence increases to 10-15% in adolescents. It is also significant among the elderly.

Depression is defined by two aspects: characteristic symptoms and their duration, which must be at least 15 days, with an impact on the patient’s personal, professional and social life.

Since the 1950s, the neurobiological basis of mood disorders such as depression has been established and has formed the basis for the development of antidepressant treatments. But it is only in the last fifteen years or so that depression has really been recognised as a disease of the brain in the same way as neurological diseases such as Parkinson’s or Alzheimer’s. The work carried out at the Institut du Cerveau – ICM by Professor Philippe Fossati (AP-HP/Sorbonne University), a psychiatrist specialising in mood disorders at the Pitié-Salpêtrière hospital and team leader at the Institut du Cerveau – ICM, has helped to demonstrate the involvement of particular brain regions in the development of depression.


How is depression characterised?

Depression is a behavioural disorder in which the mood is pathologically fixed in sadness or pain. The sadness of the depressed person is intense and is not diminished by external circumstances.

Unlike an episode of temporary sadness, a Major Depressive Episode (MDE) lasts for more than 15 days. It can lead to isolation and even suicide. The risk of death by suicide is 10 times higher for depressed people than for the rest of the population.

It is difficult for someone who is not ill to imagine depression. When we try to do so, the images that come naturally are those of sadness. We draw on painful memories from our personal history and try to remember how we felt then. However, the sadness of the depressed person is different from the usual feelings and is more intense, accompanied by other symptoms, such as anxiety and suicidal thoughts.

But depression is not just an excess of so-called negative emotions. It also has another facet, just as common and just as serious: a lack of positive affect. Psychiatrists use a variety of jargon to describe the different symptoms: anhedonia, or the inability to experience pleasure; abulia, or the abolition of willpower; apragmatism, or the inability to take action; and athymhormia, the loss of vital drive.


Last updated May 2024.