Depressive Disorders

Depression is a mood disorder in which a person loses interest or pleasure in life. Leading symptoms of depression include feeling hopeless, worthless, and a loss of energy.

Clinically speaking, depression may be diagnosed as one of several different types of depressive disorders: major depressive disorder, dysthymia, disruptive mood dysregulation disorder, premenstrual dysphoric disorder, substance/medication-induced depressive disorder, depression caused by another medical condition, or unspecified depressive disorder.

Epidemiological Factors

• Lifetime Prevalence: Major depressive disorder has the highest lifetime prevalence (almost 17 percent) of any psychiatric disorder. The lifetime prevalence rate for major depression is 5 to 17 percent.
• Sex: Major depressive disorder has a twofold greater prevalence in women than men.
• Age: The mean age of onset for major depressive disorder is about 40 years, with 50 percent of all patients having an onset between the ages of 20 and 50. Major depressive disorder can also begin in childhood or in old age. Recent data suggest that major depressive disorder may also be increasing among people younger than 20 years of age. This may be related to increased use of alcohol and drugs in this age group
• Marital Status: Major depressive disorder occurs most often in persons without close interpersonal relationships and in those who are divorced or separate.
• Socioeconomic & Cultural Factors: No correlation has been found between socioeconomic status and major depressive disorder. Depression is more common in rural areas than in urban areas. The prevalence of mood disorder does not differ among races.

Major depressive disorder (clinical depression) is diagnosed when a person experiences a depressed mood or a loss of interest or pleasure with feelings of sadness, emptiness or hopelessness on most days during at least a two-week period. Children or adolescents may demonstrate irritability. In addition, a diagnosis for major depressive disorder requires at least four of the following symptoms to be experienced on most days:

• Fatigue or loss of energy
• Restlessness or lethargy
• Feelings of worthlessness or excessive guilt
• Recurrent suicidal thoughts or attempted suicide
• Diminished ability to think, concentrate, or to make decisions.
• Insomnia (inability to sleep) or sleeping too much
• Significant weight loss or weight gain comprising more than 5 percent of one’s body weight in a month’s time, or a change in appetite nearly every day. In children, expected weight gain may not occur.

Dysthymia, also known as persistent depressive disorder, is less severe than major depressive disorder. It is characterized by a depressed mood for most of the day, on more days than not, for at least two years. In addition, dysthymia is diagnosed when a person experiences two or more of the following symptoms:

• Poor appetite or overeating
• Insomnia or sleeping too much
• Low energy or fatigue
• Low self-esteem
• Poor concentration or difficulty making decisions
• Feelings of hopelessness

Disruptive mood dysregulation disorder is characterized by severe recurrent temper outbursts expressed verbally and/or behaviorally. A person with this disorder will show physical aggression toward people or property that is grossly out of proportion in intensity or duration to the situation or provocation. The temper outbursts occur, on average, three or more times per week and are inconsistent with the individual’s developmental level. Moreover, the individual’s mood between temper outbursts is persistently irritable or angry most of the day, nearly every day.

A diagnosis for this condition may occur when:

• Symptoms and behavior described above have been present for 12 or more months, including a lapse of symptoms for no more than 3 months.
• Behaviors do not occur exclusively during an episode of major depressive disorder and are not better explained by another mental disorder, such as autism, posttraumatic stress disorder, separation anxiety disorder, or dysthymia.
• Symptoms are not attributable to the physiological effects of a substance or to another medical or neurological condition.

A diagnosis for disruptive mood dysregulation disorder cannot coexist with a diagnosis of oppositional defiant disorder, intermittent explosive disorder, or bipolar disorder. However, it can coexist with major depressive disorder, attention deficit hyperactivity disorder (ADHD), conduct disorder, and substance abuse disorders.

Premenstrual dysphoric disorder is a condition similar to Premenstrual Syndrome (PMS), but it is more serious. This type of depression is diagnosed when at least five symptoms are experienced in the final week before the onset of a woman’s menstrual period. The symptoms improve within a few days after a woman’s period begins and become minimal or absent in the week after her period ends. Among the symptoms listed below, at least one symptom must be present from symptoms 1-4, and at least one from symptoms 5-11:

1. Mood swings, feeling suddenly sad or tearful, or an increased sensitivity to rejection
2. Irritability, anger, or increased interpersonal conflicts
3. Depressed mood, feelings of hopelessness, or self-deprecating thoughts
4. Anxiety, tension, or feelings of being on-edge
5. Decreased interest in usual activities (work, school, friends, hobbies)
6. Difficulty concentrating
7. Lethargy or lack of energy
8. Change in appetite, overeating, or specific food cravings
9. Insomnia or sleeping too much
10. Feeling overwhelmed or out of control
11. Physical symptoms such as breast tenderness or swelling, joint or muscle pain, feeling bloated, or weight gain

Substance/medication-induced depressive disorder occurs when a person experiences a depressed mood, or greatly diminished interest or pleasure in activities, during or after substance intoxication or withdrawal, or after taking a medication. Substances that can cause depression include alcohol, cocaine, opioids, sedatives, amphetamines, inhalants, phencyclidine, or other substances.

A person can be diagnosed with depressive disorder due to another medical condition when there is evidence from the history, physical examination, or laboratory findings that the depression is the direct consequence of another medical condition. Requirements for this diagnosis also include:

• A prominent and persistent period of depressed mood in all, or almost all, activities.
• The depression is not better explained by another mental disorder, such as adjustment disorder, in which the stressor is a serious medical condition.
• The depression does not occur exclusively during the course of a delirium.
• The individual experiences significant distress or impairment in social, occupational, or other important areas of functioning.

A diagnosis of “unspecified depressive disorder” is used when symptoms of depression cause significant distress or impairment in social, occupational, or other important areas of functioning but do not meet the full criteria for any of the depressive disorder diagnoses. This diagnosis may be used with any of the following groups of symptoms:

• With anxious distress, defined as at least 2 of the following symptoms during the majority of days of a major depressive episode or dysthymia:
  o Feeling keyed up or tense
  o Feeling unusually restless
  o Difficulty concentrating because of worry
  o Fear that something awful may happen
  o Feeling that the individual may lose control of himself or herself
  
• With manic/hypomanic symptoms, when at least 3 of the following symptoms are present nearly every day during a major depressive episode and are not attributable to the effects of a substance (a drug of abuse, medication, or other treatment):
  o Elevated, expansive mood
  o Inflated self-esteem or grandiosity
  o More talkative than usual or pressure to keep talking
  o Flight of ideas or racing ideas
  o Increase in energy or goal-directed activity
  o Increased or excessive involvement in activities that have a high potential for painful consequences, such as engaging in unrestrained buying sprees, sexual indiscretions, foolish business investments.
  o Decreased need for sleep (feeling rested despite sleeping less than usual)
  
• With melancholic features, when one of the following is present during the most severe period of the depressive episode:
  o Loss of pleasure in all, or almost all, activities
  o Lack of reactivity to usually pleasurable stimuli (does not feel much better, even temporarily, when something good happens)
  
  In addition, 3 or more of the following symptoms are present:
  o A depressed mood characterized by profound despondency, despair, or a so-called empty mood
  o Depression that is regularly worse in the morning
  o Early-morning awakening, at least 2 hours before usual wakening
  o Significant anorexia or weight loss
  o Excessive or inappropriate guilt
  
• Atypical symptoms may qualify for a diagnosis of depressive disorder when an individual experiences the following features during the majority of days:
  o Mood brightens in response to positive events
  o Two or more of the following:
  • Significant weight gain or increase in appetite
  • Hypersomnia (excessive sleeping)
  • Heavy, leaden feelings in arms or legs
  • Long-standing pattern of interpersonal rejection sensitivity that results in significant social or occupational impairment
  
• Other features that may characterize a diagnosis for the unspecified depressive disorder include:
  o Delusions and/or hallucinations
  o Catatonia (abnormal movement and behavior arising from a disturbed mental state, typically schizophrenia)
  o Peripartum onset, if the most recent episode of major depression occurs during pregnancy or in the 4 weeks following delivery
  o Postpartum depression, which may occur with or without psychotic features
  o Seasonal patterns, when major depressive episodes occur during a particular time of the year, such as fall or winter

Thyroid dysfunction can be a direct cause of depression.

Depression may be associated with the development of heart disease, stroke, diabetes, hypertension, hyperlipidemia, obesity, and autoimmune diseases such as multiple sclerosis or lupus. It also causes poor outcomes from these conditions.

Depression may increase the likelihood of smoking, drug or alcohol use, lack of physical activity, and lack of social contact with others.

Yes, women are two times more likely to experience depression than men, despite the country or culture that they live in. Reasons for this difference are thought to involve hormonal differences, the effects of childbirth, different psychosocial stressors for women and for men, and, for some women, behavioral models of learned helplessness.

No, there is no association with an increase in depression and a person’s age.The average age of onset for major depressive disorder is about 40 years, with 50 percent of all patients experiencing a major depressive disorder between the ages of 20 and 50. Recent data suggests that major depressive disorder may also be increasing among people younger than 20 years of age. This may be related to an increased use of alcohol and drugs in this age group.

Major depressive disorder occurs most often in individuals who have divorced or separated, or those without close interpersonal relationships.

Yes, approximately 5-10 percent of people evaluated for depression have previously undetected thyroid dysfunction. Thyroid dysfunction is reflected by an elevated basal thyroid-stimulating hormone (TSH) level found in laboratory tests. Such abnormalities are often associated with elevated anti-thyroid antibody levels. Unless corrected with hormone replacement therapy, this problem can compromise a person’s response to antidepressant medication treatment.

In addition, approximately 20-30 percent of depressed patients show a blunted TSH response, indicating an increased risk for relapsing into depression despite preventative antidepressant therapy. This problem is more difficult to treat.

Yes, clinically depressed individuals often have shortened cycles of deep sleep and are more easily awakened. Some younger depressed patients may have the opposite experience and sleep longer than normal. Patients with an abnormal sleep profile have found to be less responsive to psychotherapy and may benefit more from antidepressant medication.

Yes, depressive disorders are associated with several elements of immune dysfunction. This includes lower levels of lymphocytes, which are types of white blood cells responsible for the body’s ability to fight off infections. That’s why it’s so important to take care of one’s mental health, as well as one’s physical health.

Yes, people who excessively use drugs to alter their mental state (such as alcohol, narcotics, or cocaine) are more likely to experience depression.

Yes, individuals who experience social anxiety disorder and/or panic attacks have an increased risk of depression.

Yes, women are two times more likely than men to experience depression overall. In addition, there are other different risk factors between men and women when it comes to depression. Men with substance abuse problems more frequently experience depression than women who abuse drugs. Meanwhile, women with anxiety or eating disorders more frequently become clinically depressed than men with these same issues.

Depression, in most cases, is caused by a combination of multiple factors. These factors can include genetic susceptibility, live events, environmental stress, and psychodynamic considerations.

Biological Factors

• Neurotransmitter Disturbances
  Norepinephrine and serotonin are the two neurotransmitters most implicated in mood disorders. Dopamine is also thought to play a role.
• Hormonal Dysregulation
  Approximately 5 to 10 percent of depression patients have previously undetected thyroid dysfunction.
• Sleep Neurophysiology
  Depression is associated with a premature loss of deep (slow-wave) sleep and in increase in sleep awakening at night.
• Neuroanatomical Considerations
  Modern neuroscience focuses on four regions of the brain responsible for the regulation of normal emotions: the prefrontal cortex, the anterior cingulate, the hippocampus, and the amygdala. Physical trauma to the brain, therefore, could be a factor in depression.• Immunological Issues
  Depressive disorders are associated with several immunological abnormalities. (More info in Q&A)

Genetic Factors
Studies indicate that if one parent has a mood disorder, such as major depressive disorder, their child will have a 10 to 25 percent risk for a mood disorder. If both parents are affected, the risk for their child approximately doubles. In addition, the more members of a family that are affected by a mood disorder the greater the risk is to a child.

Studies of twins provide evidence that genes account for 50 to 70 percent of genetic mood disorders. Environmental or other factors are thought to account for the remainder. Studies showthat the rate of mood disorders shared by twins is higher among identical twins (70 to 90 percent) than among fraternal twins (16 to 35 percent).

Psychosocial Factors

• Life Events and Environmental Stress
  Stressful life events are shown to more often precede first, rather than subsequent, episodes of depression. One theory is that the stress accompanying the first episode of depression results in long-lasting changes in the brain’s biology, which may alter neurotransmitter functioning. As a result, a person is at risk for experiencing subsequent episodes of depression, even without an external stressor. Some experts believe that life events play the primary role in depression. The strongest evidence to support this theory is when children under the age of 11 lose a parent and experience major depression. Losing a spouse is the life event most often associated with the onset of depression. Another risk factor is unemployment. People who are out of work are three times more likely to report symptoms of major depression than those who are employed.
• Personality Factors
  There is no evidence that any particular personality type or trait predisposes a person to depression. All people, of any personality type, can and do become depressed under appropriate circumstances, such as job loss, traumatic events, major life change, loss of a loved one, persistent abuse by another, or drug/substance abuse.
• Psychodynamic Factors
  Psychodynamic factors take into account the unconscious psychological forces that impact a person’s psychological development. When it comes to depression, there are several different psychodynamic theories. Theories range from a disturbed infant-mother relationship (Sigmond Freud), an expression of aggression toward loved ones (Melanie Klein), living for someone else rather than oneself (Silvano Arieti), an expression of powerlessness (Edith Jacobson), a lack of self-esteem due to emotional needs unmet by parents (Heinz Kohut), traumatic separation during childhood or damaged early attachments (John Bowlby).

Cognitive Theory
Cognitive theory asserts that depression can develop in individuals with cognitive distortions (inaccurate thoughts), such as negative perceptions towards themselves, the world, and their future (Aaron Beck). Depressed patients may have cognitive distortions, drawing a specific conclusion without sufficient evidence. They may also focus on a single detail while ignoring other, more important aspects of an experience. Likewise, they may form conclusions based on limited experience, or they may overvalue or undervalue the significance of a particular event.

Learned Helplessness
The learned helplessness theory connects depression to the experience of uncontrollable events. Adverse external events cause a loss of self-esteem, leading to depression. Behaviorists who subscribe to this theory believe that improving one’s depression in such a case depends on the patient learning a sense of control and mastery of one’s environment.

Treatment for depression can involve several strategies. Most studies indicate that a combination of psychotherapy and antidepressant medication is the most effective treatment for major depressive disorder. Either medication or psychotherapy alone is effective in treating patients with mild depression.

There are several groups of antidepressants that are used to treat depression:

• Selective serotonin reuptake inhibitor (SSRI) drugs work by increasing levels of serotonin in the brain. These commonly used medications include Zoloft, Prozac, Paxil, Lexapro, etc.
• Serotonin norepinephrine reuptake inhibitor (SNRI) drugs increase levels of serotonin and norepinephrine in the brain. These commonly used medications include Effexor, Cymbalta, Pristiq, etc.
• Tricyclic, or cyclic, antidepressants (TCA) are less commonly used today. Introduced in the late 1950s, they act on approximately five different neurotransmitter pathways to achieve their effects. These drugs are a good choice for patients who are resistant to other antidepressant medications. They include Nortriptyline, Amitriptyline,Clomipramine, etc.
• Monoamine oxidase inhibitors (MAOI) mediations inhibit the activity of one or both monoamine oxidase enzymes. Introduced in the 1950s as the first drugs to treat depression, they are rarely used today.

Cognitive Behavioral Therapy (CBT) – Short Term Therapy
The goal of cognitive behavioral therapy is to change patterns of thinking or behaviors associated with people’s difficulties, resulting in improving the way they feel. CBT works by changing people’s attitudes, behaviors, and how they deal with emotional problems by focusing on their thoughts, images, beliefs and attitudes. Most studies have found that cognitive behavioral therapy is as effective as medication in treating major depressive disorder.

Interpersonal Therapy – Short Term Therapy
Interpersonal therapy, developed by Gerald Klerman, focuses on one or two of a patient’s current interpersonal problems. During the course of treatment, therapy may address a patient’s defense mechanisms, internal conflicts, lack of assertiveness, limited social skills, or distorted thinking.

Supportive Psychotherapy -- Short to Long Term Therapy
This is a type of psychotherapy that integrates various components of psychodynamic, CBT and interpersonal psychotherapy. It helps to improve symptoms and to maintain, restore, or improve self-esteem, ego functions, and adaptive skills.

Psychodynamic Psychotherapy -- Short to Long Term
The goal of this psychotherapy is to study the psychological forces that underlie human behavior, feelings, and emotions and how they might relate to early experiences. Psychodynamic psychotherapy works to uncover repressed childhood experiences that are thought to explain an individual’s current difficulties.

Psychoanalytic Psychotherapy – Long Term Therapy
The goal of psychoanalytic psychotherapy is to effect a change in an individual’s personality or character, such as improving interpersonal trust, capacity for intimacy, coping mechanisms, the capacity to grieve, and the ability to experience a wide range of emotions. Treatment may continue for several years.

Family Therapy– Short Term Therapy
Family therapy is not generally viewed as primary therapy for the treatment of the major depressive disorder. However, family therapy will be considered if the depression jeopardizes the functioning of a patient’s marriage or family, or if the depression is promoted or maintained by the family situation.

A certain number of patients may have treatment-resistant depression, meaning they do not get better with medication and therapy. For these patients, treatments including transcranial magnetic stimulation (TMS) or electroconvulsive therapy (ECT) can help.