Depression is a mental illness that can encompass persistent feelings of sadness, difficulties adjusting to low moods, and major depressive disorders (MDD). MDDs affect 8 percent of Canadians, and can occur in 10 to 25 percent of women—twice the rate at which it affects men. Such disorders are persistent and can significantly interfere with an individual's thoughts, behaviour, mood, energy and motivation, activity, and physical health. Depression tends to be episodic; more than half of the individuals who experience a single episode of MDD will continue to have episodes as frequently as once or even twice a year. Without treatment, the frequency and severity of MDD tends to increase over time. Left untreated, individuals with MDD are prone to having thoughts about taking their lives (referred to as “suicidal ideation"); a significant percentage of people with MDD die by suicide.

Depression differs from the commonly experienced “dip" in mood that may accompany a disappointment in the following ways:

  • It lasts more than two weeks and is persistent
  • It is more disruptive:
    • Interferes with ability to work/study and to have satisfying relationships
    • Causes physical symptoms and affects thoughts, emotions, and behaviours
  • It often appears to lack precipitants or “triggers"

Symptoms of MDD

The onset of the first episode of major depression may not be obvious if it is gradual or if the symptoms are mild. The symptoms of MDD characteristically represent a significant change from how a person usually functions. The symptoms include:

  • Persistently sad or irritable mood
  • Pronounced changes in sleep, appetite, and energy
  • Difficulty thinking, concentrating, and remembering
  • Physical lethargy or agitation
  • Lack of interest in or pleasure from activities that were once enjoyed
  • Feelings of guilt, worthlessness, hopelessness, and emptiness
  • Recurrent thoughts of death or suicide
  • Persistent physical symptoms that do not respond to treatment, such as headaches, digestive disorders, and chronic pain

When several of these symptoms of depressive illness occur at the same time, last longer than two weeks, and interfere with ordinary functioning, professional treatment is needed.

How is MDD treated?

Although MDD can be devastating, it is highly treatable. Between 80 and 90 percent of those diagnosed with MDD benefit from effective treatments and return to their daily activities. Many treatments are available, and the type chosen depends on the individual and the severity and patterns of her/his illness. Common treatments include medication, psychotherapy, or a combination of both. Additionally, peer education and social support can promote recovery. Good self-care—including attention to diet, exercise, and sleep—can result in not only better physical health but also better mental health.

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