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 once enjoyed. It can lead to a variety of emotional and physical problems and can decrease a person’s ability to function at work and at home.
Diagnostic Criteria for Major Depressive Disorder and Depressive Episodes
DSM-IV Criteria for Major Depressive Disorder (MDD)
• Depressed mood or a loss of interest or pleasure in daily activities for more than two weeks.
• Mood represents a change from the person’s baseline.
• Impaired function: social, occupational, educational.
Specific symptoms, at least 5 of these 9, present nearly every day:
1. Depressed mood or irritable most of the day, nearly every day, as indicated by either subjective report(e.g., feels sad or empty) or observation made by others (e.g., appears tearful).
2. Decreased interest or pleasure in most activities, most of each day
3. Significant weight change (5%) or change in appetite
4. Change in sleep: Insomnia or hypersomnia
5. Change in activity: Psychomotor agitation or retardation
6. Fatigue or loss of energy
7. Guilt/worthlessness: Feelings of worthlessness or excessive or inappropriate guilt
8. Concentration: diminished ability to think or concentrate, or more indecisiveness
9. Suicidality: Thoughts of death or suicide, or has suicide plan
Symptoms must last at least two weeks for a diagnosis of depression.
Types and symptoms
Depending on the number and severity of symptoms, a depressive episode can be categorized as mild, moderate or severe.
A key distinction is also made between depression in people who have or do not have a history of manic episodes. Both types of depression can be chronic (i.e. over an extended period) with relapses, especially if they go untreated.
Recurrent depressive disorder: this disorder involves repeated depressive episodes. During these episodes, the person experiences depressed mood, loss of interest and enjoyment, and reduced energy leading to diminished activity for at least two weeks. Many people with depression also suffer from anxiety symptoms, disturbed sleep and appetite, and may have feelings of guilt or low self-worth, poor concentration and even symptoms that cannot be explained by a medical diagnosis.
Depending on the number and severity of symptoms, a depressive episode can be categorized as mild, moderate or severe. An individual with a mild depressive episode will have some difficulty in continuing with ordinary work and social activities but will probably not cease to function completely. During a severe depressive episode, it is unlikely that the sufferer will be able to continue with social, work or domestic activities, except to a limited extent.
Bipolar affective disorder: this type of depression typically consists of both manic and depressive episodes separated by periods of normal mood. Manic episodes involve elevated or irritable mood, over-activity, pressure of speech, inflated self-esteem and a decreased need for sleep.
Contributing factors and prevention
Depression results from a complex interaction of social, psychological and biological factors. People who have gone through adverse life events (unemployment, bereavement, psychological trauma) are more likely to develop depression. Depression can, in turn, lead to more stress and dysfunction and worsen the affected person’s life situation and depression itself.
There are interrelationships between depression and physical health. For example, cardiovascular disease can lead to depression and vice versa.
Prevention programs have been shown to reduce depression. Effective community approaches to prevent depression include school-based programs to enhance a pattern of positive thinking in children and adolescents. Interventions for parents of children with behavioral problems may reduce parental depressive symptoms and improve outcomes for their children. Exercise programs for the elderly can also be effective in depression prevention.
Diagnosis and treatment
There are effective treatments for moderate and severe depression. Health-care providers may offer psychological treatments such as behavioural activation, cognitive behavioural therapy (CBT) and interpersonal psychotherapy (IPT), or antidepressant medication such as selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs). Health-care providers should keep in mind the possible adverse effects associated with antidepressant medication, the ability to deliver either intervention (in terms of expertise, and/or treatment availability), and individual preferences. Different psychological treatment formats for consideration include individual and/or group face-to-face psychological treatments delivered by professionals and supervised lay therapists.
Psychosocial treatments are also effective for mild depression. Antidepressants can be an effective form of treatment for moderate-severe depression but are not the first line of treatment for cases of mild depression. They should not be used for treating depression in children and are not the first line of treatment in adolescents, among whom they should be used with extra caution.
Source: World Health Association.