Depression (mood)

Depression
A man diagnosed as suffering from melancholia with strong su Wellcome L0026693.jpg
Lithograph of a man diagnosed as suffering from melancholia with strong suicidal tendency (1892)
SpecialtyPsychiatry

Depression is a state of low mood and aversion to activity. It can affect a person's thoughts, behavior, motivation, feelings, and sense of well-being. It may feature sadness, difficulty in thinking and concentration and a significant increase or decrease in appetite and time spent sleeping. People experiencing depression may have feelings of dejection, hopelessness and, sometimes, suicidal thoughts. It can either be short term or long term.[1] The core symptom of depression is said to be anhedonia, which refers to loss of interest or a loss of feeling of pleasure in certain activities that usually bring joy to people.[2] Depressed mood is a symptom of some mood disorders such as major depressive disorder or dysthymia;[3] it is a normal temporary reaction to life events, such as the loss of a loved one; and it is also a symptom of some physical diseases and a side effect of some drugs and medical treatments.

Factors

Life events

Adversity in childhood, such as bereavement, neglect, mental abuse, physical abuse, sexual abuse, and unequal parental treatment of siblings can contribute to depression in adulthood.[4][5] Childhood physical or sexual abuse in particular significantly correlates with the likelihood of experiencing depression over the victim's lifetime.[6]

Life events and changes that may influence depressed moods include (but are not limited to): childbirth, menopause, financial difficulties, unemployment, stress (such as from work, education, family, living conditions etc.), a medical diagnosis (cancer, HIV, etc.), bullying, loss of a loved one, natural disasters, social isolation, rape, relationship troubles, jealousy, separation, and catastrophic injury.[7][8][9] Adolescents may be especially prone to experiencing depressed mood following social rejection, peer pressure, or bullying.[10]

Personality

Changes in personality or in ones social environment can affect levels of depression. High scores on the personality domain neuroticism make the development of depressive symptoms as well as all kinds of depression diagnoses more likely,[11] and depression is associated with low extraversion.[12] Other personality indicators could be: temporary but rapid mood changes, short term hopelessness, loss of interest in activities that used to be of a part of one's life, sleep disruption, withdrawal from previous social life, appetite changes, and difficulty concentrating.[13]

Medical treatments

Depression may also be the result of healthcare, such as with medication induced depression. Therapies associated with depression include interferon therapy, beta-blockers, isotretinoin, contraceptives,[14] cardiac agents, anticonvulsants, antimigraine drugs, antipsychotics, and hormonal agents such as gonadotropin-releasing hormone agonist.[15]

Substance-induced

Several drugs of abuse can cause or exacerbate depression, whether in intoxication, withdrawal, and from chronic use. These include alcohol, sedatives (including prescription benzodiazepines), opioids (including prescription pain killers and illicit drugs such as heroin), stimulants (such as cocaine and amphetamines), hallucinogens, and inhalants.[16]

Non-psychiatric illnesses

Depressed mood can be the result of a number of infectious diseases, nutritional deficiencies, neurological conditions[17] and physiological problems, including hypoandrogenism (in men), Addison's disease, Cushing's syndrome, hypothyroidism, Lyme disease, multiple sclerosis, Parkinson's disease, chronic pain, stroke,[18] diabetes,[19] and cancer.[20]

Psychiatric syndromes

A number of psychiatric syndromes feature depressed mood as a main symptom. The mood disorders are a group of disorders considered to be primary disturbances of mood. These include major depressive disorder (MDD; commonly called major depression or clinical depression) where a person has at least two weeks of depressed mood or a loss of interest or pleasure in nearly all activities; and dysthymia, a state of chronic depressed mood, the symptoms of which do not meet the severity of a major depressive episode. Another mood disorder, bipolar disorder, features one or more episodes of abnormally elevated mood, cognition and energy levels, but may also involve one or more episodes of depression.[21] When the course of depressive episodes follows a seasonal pattern, the disorder (major depressive disorder, bipolar disorder, etc.) may be described as a seasonal affective disorder. Outside the mood disorders: borderline personality disorder often features an extremely intense depressive mood; adjustment disorder with depressed mood is a mood disturbance appearing as a psychological response to an identifiable event or stressor, in which the resulting emotional or behavioral symptoms are significant but do not meet the criteria for a major depressive episode;[22]:355 and posttraumatic stress disorder, a mental disorder that sometimes follows trauma, is commonly accompanied by depressed mood.[23]

Historical legacy

Researchers have begun to conceptualize ways in which the historical legacies of racism and colonialism may create depressive conditions.[24][25]