Depression is a mood disorder marked by feelings of acute sadness, hopelessness, and
helplessness. Individuals may experience changes in sleep, appetite, or sexual desire. They lose interest in regular activities and may be unable to experience feelings of pleasure. Changes may be either an increase or decrease. Depression may progress to the point that people commit suicide due to the symptoms and intolerable pain related to chronic, severe depression.
According to the DSM-IV-TR (2001), depression is characterized by the presence of symptoms over a two-week period of time and a significant change from the individual's previous level of function. The person must demonstrate either depressed mood or reduced interest in activity and pleasure. These feelings cause reduced ability to function. Criteria include:
- Depressed mood most of the day every day, characterized by feelings of sadness or emptiness
- Reduced interest in activities and reduced pleasure in activities most of the day, every day
- Significant weight loss or weight gain in a month (5%)
- Inability to sleep or sleeping all the time (insomnia or hypersomnia)
- Observed behaviors of either restlessness (agitation) or slowed movement nearly every day
- Fatigue or energy loss
- Feelings of worthlessness or inappropriate guilt nearly every day
- Reduced ability to think or concentrate nearly every day
- Recurring thoughts of death and recurring thoughts of suicide
Depression can result from a number of causes and is influenced by genetic, environmental, and neurobiological factors. Sometimes no explanation is apparent. Depression is considered by some to be a biochemical illness resulting from an imbalance in neurochemicals and hormones in the brain (e.g., norepinephrine, dopamine). Stress causes effects in the body, brain, and immune system. The stress hormone, glucocorticoid, interacts with serotonin during times of stress. Systems of the brain affected by these neurochemical changes regulate arousal, sleep, appetite, mood, and the capacity to experience pleasure (i.e., primary symptoms of depression).
Other potential causes of depression include: belief systems resulting in negative thinking patterns, patterned ways of interpreting life events, substance use and other addictions, certain illnesses, and medications. A family history of depression places a person at increased risk. Sometimes difficult situations and life events, such as divorce or financial problems, causes depression. Depression is one of the stages of the grief process.
Depression is one of the common reactions to the disclosure of a child's sexual abuse. Healthy coping and changing the lifestyle to counteract stress will decrease the potential to develop depression and reduce depression symptoms already present.