Depression is a mental health disorder that is characterised by a persistently low mood, including a feeling of overwhelming sadness and loss of interest. It is a persistent problem that does not pass by as quickly as most people think. The average length of depression can last between 6 and eight months.

Depression is different from the fluctuations in mood that is experienced as part of a normal, healthy life. Temporary emotional responses to the challenges of everyday life, does not constitute depression. The same goes for temporary grief resulting from the death of a loved one, even though depression can be the result of bereavement.

The causes of depression are not fully understood and may not be down to a single source. However, depression is due to a combination of factors that include genetics, biological changes and the environment. People at a higher risk of developing depression may experience the following risk factors:

  • Life events - for example, bereavement, divorce, and poverty
  • Personality - less successful coping strategies, for instance
  • Genetic factors - first-degree relatives of depressed patients are at higher risk
  • Childhood trauma
  • Some prescription drugs - including corticosteroids, some beta-blockers, interferon, and reserpine
  • Abuse of recreational drugs - can accompany depression or result in it. There are strong links between drug abuse and depression
  • A past head injury
  • People who have had an episode of major depression are at higher risk of a subsequent one
  • Chronic pain syndromes in particular, but also other chronic conditions, such as diabetes, chronic obstructive pulmonary disease, and cardiovascular disease

People who are suffering from depression may present the following signs and symptoms:

  • Depressed mood
  • Reduced interest or pleasure in activities previously enjoyed, loss of sexual desire
  • Unintentional weight loss (without dieting) or low appetite
  • Insomnia (difficulty sleeping) or hypersomnia (excessive sleeping)
  • Psychomotor agitation (for example, restlessness, pacing up and down), or psychomotor retardation (slowed movements and speech)
  • Fatigue or loss of energy
  • Feelings of worthlessness or guilt
  • Worsened ability to think, concentrate, or make decisions
  • Recurrent thoughts of death or suicide, or attempt at suicide
  • Appearing miserable, tearful eyes, furrowed brows, down-turned corners of the mouth
  • Slumped posture, lack of eye contact and facial expression
  • Little body movement, and speech changes
  • Gloomy, pessimistic, humourless, passive, lethargic, introverted, hypercritical of self and others, complaining