What Is Depression?

Depression (major depressive disorder) is a common and serious medical illness that negatively affects how you feel, the way you think and how you act. Fortunately, it is also treatable. Depression causes feelings of sadness and/or a loss of interest in activities you once enjoyed. It can lead to a variety of emotional and physical problems and can decrease your ability to function at work and at home.

Depression symptoms can vary from mild to severe and can include:

  • Feeling sad or having a depressed mood
  • Loss of interest or pleasure in activities once enjoyed
  • Changes in appetite — weight loss or gain unrelated to dieting
  • Trouble sleeping or sleeping too much
  • Loss of energy or increased fatigue
  • Increase in purposeless physical activity (e.g., inability to sit still, pacing, handwringing) or slowed movements or speech (these actions must be severe enough to be observable by others)
  • Feeling worthless or guilty
  • Difficulty thinking, concentrating or making decisions
  • Thoughts of death or suicide

CHRONIC AND ACUTE STRESS AND THE PREDICTION OF MAJOR DEPRESSION IN WOMEN 

Much evidence validates the link between onset of a major depressive episode (MDE) and prior stressful life events, particularly major undesirable events.[13] However, the predominant research focus is on episodic (acute) life events, and commonly ignores the co-occurring effects of chronic, ongoing stressful conditions on depression. Examining episodic events that have relatively discreet beginnings and endings may tell only part of the story of the stress–depression association, as stressful life events occur within the ongoing conditions of a person’s life. For many, daily life experiences include continuing negative environmental circumstances (chronic stress) such as poor working conditions; financial difficulties; absent, intermittently or chronically unfulfilling or conflictual intimate relationships with romantic partners, parents, children, or friends; continuing health problems; and other ongoing burdens.