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

Symptoms must last at least two weeks and must represent a change in your previous level of functioning for a diagnosis of depression.

Also, medical conditions (e.g., thyroid problems, a brain tumor or vitamin deficiency) can mimic symptoms of depression so it is important to rule out general medical causes.

Depression affects an estimated one in 15 adults (6.7%) in any given year. And one in six people (16.6%) will experience depression at some time in their life. Depression can occur at any time, but on average, first appears during the late teens to mid-20s. Women are more likely than men to experience depression. Some studies show that one-third of women will experience a major depressive episode in their lifetime. There is a high degree of heritability (approximately 40%) when first-degree relatives (parents/children/siblings) have depression.

Depression Is Different From Sadness or Grief/Bereavement

The death of a loved one, loss of a job or the ending of a relationship are difficult experiences for a person to endure. It is normal for feelings of sadness or grief to develop in response to such situations. Those experiencing loss often might describe themselves as being “depressed.”

But being sad is not the same as having depression. The grieving process is natural and unique to each individual and shares some of the same features of depression. Both grief and depression may involve intense sadness and withdrawal from usual activities. They are also different in important ways:

  • In grief, painful feelings come in waves, often intermixed with positive memories of the deceased. In major depression, mood and/or interest (pleasure) are decreased for most of two weeks.
  • In grief, self-esteem is usually maintained. In major depression, feelings of worthlessness and self-loathing are common.
  • In grief, thoughts of death may surface when thinking of or fantasizing about “joining” the deceased loved one. In major depression, thoughts are focused on ending one’s life due to feeling worthless or undeserving of living or being unable to cope with the pain of depression.

Grief and depression can co-exist For some people, the death of a loved one, losing a job or being a victim of a physical assault or a major disaster can lead to depression. When grief and depression co-occur, the grief is more severe and lasts longer than grief without depression. 

Distinguishing between grief and depression is important and can assist people in getting the help, support or treatment they need.

Risk Factors for Depression

Depression can affect anyone—even a person who appears to live in relatively ideal circumstances.

Several factors can play a role in depression:

  • Biochemistry: Differences in certain chemicals in the brain may contribute to symptoms of depression.
  • Genetics: Depression can run in families. For example, if one identical twin has depression, the other has a 70 percent chance of having the illness sometime in life.
  • Personality: People with low self-esteem, who are easily overwhelmed by stress, or who are generally pessimistic appear to be more likely to experience depression.
  • Environmental factors: Continuous exposure to violence, neglect, abuse or poverty may make some people more vulnerable to depression.

How Is Depression Treated?

Depression is among the most treatable of mental disorders. Between 80% and 90% percent of people with depression eventually respond well to treatment. Almost all patients gain some relief from their symptoms.

Before a diagnosis or treatment, a health professional should conduct a thorough diagnostic evaluation, including an interview and a physical examination. In some cases, a blood test might be done to make sure the depression is not due to a medical condition like a thyroid problem or a vitamin deficiency (reversing the medical cause would alleviate the depression-like symptoms). The evaluation will identify specific symptoms and explore medical and family histories as well as cultural and environmental factors with the goal of arriving at a diagnosis and planning a course of action.

Medication: Brain chemistry may contribute to an individual’s depression and may factor into their treatment. For this reason, antidepressants might be prescribed to help modify one’s brain chemistry. These medications are not sedatives, “uppers” or tranquilizers. They are not habit-forming. Generally antidepressant medications have no stimulating effect on people not experiencing depression.

Antidepressants may produce some improvement within the first week or two of use yet full benefits may not be seen for two to three months. If a patient feels little or no improvement after several weeks, his or her psychiatrist can alter the dose of the medication or add or substitute another antidepressant. In some situations other psychotropic medications may be helpful. It is important to let your doctor know if a medication does not work or if you experience side effects.

Psychiatrists usually recommend that patients continue to take medication for six or more months after the symptoms have improved. Longer-term maintenance treatment may be suggested to decrease the risk of future episodes for certain people at high risk.

Psychotherapy: Psychotherapy, or “talk therapy,” is sometimes used alone for treatment of mild depression; for moderate to severe depression, psychotherapy is often used  along with antidepressant medications. Cognitive behavioral therapy (CBT) has been found to be effective in treating depression. CBT is a form of therapy focused on the problem solving in the present. CBT helps a person to recognize distorted/negative thinking with the goal of changing thoughts and behaviors to respond to challenges in a more positive manner.

Psychotherapy may involve only the individual, but it can include others. For example, family or couples therapy can help address issues within these close relationships. Group therapy brings people with similar illnesses together in a supportive environment, and can assist the participant to learn how others cope in similar situations .

.Depending on the severity of the depression, treatment can take a few weeks or much longer. In many cases, significant improvement can be made in 10 to 15 sessions.

Electroconvulsive Therapy (ECT) is a medical treatment that has been most commonly reserved for patients with severe major depression who have not responded to other treatments. It involves a brief electrical stimulation of the brain while the patient is under anesthesia. A patient typically receives ECT two to three times a week for a total of six to 12 treatments. It is usually managed by a team of trained medical professionals including a psychiatrist, an anesthesiologist and a nurse or physician assistant. ECT has been used since the 1940s, and many years of research have led to major improvements and the recognition of its effectiveness as a mainstream rather than a “last resort” treatment. . 

Self-help and Coping

There are a number of things people can do to help reduce the symptoms of depression. For many people, regular exercise helps create positive feeling and improves mood. Getting enough quality sleep on a regular basis, eating a healthy diet and avoiding alcohol (a depressant) can also help reduce symptoms of depression.

Depression is a real illness and help is available. With proper diagnosis and treatment, the vast majority of people with depression will overcome it. If you are experiencing symptoms of depression, a first step is to see your family physician or psychiatrist. Talk about your concerns and request a thorough evaluation. This is a start to addressing your mental health needs.

Related Conditions

Premenstrual Dysphoric Disorder

Premenstrual dysphoric disorder (PMDD) was added to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013. A woman with PMDD has severe symptoms of depression, irritability, and tension about a week before menstruation begins.

Common symptoms include mood swings, irritability or anger, depressed mood,  and marked anxiety or tension. Other symptoms may include decreased interest in usual activities, difficulty concentrating, lack of energy or easy fatigue, changes in appetite with specific food cravings, trouble sleeping or sleeping too much, or a sense of being overwhelmed or out of control. Physical symptoms may include breast tenderness or swelling, joint or muscle pain, a sensation of “bloating,” or weight gain.

These symptoms begin a week to 10 days before the start of menstruation and improve or stop around the onset of menses. The symptoms lead to significant distress and problems with regular functioning or social interactions.

For a diagnosis of PMDD, symptoms must have occurred in most of the menstrual cycles during the past year and must have an adverse effect on work or social functioning. Premenstrual dysphoric disorder is estimated to affect between 1.8% to 5.8% of menstruating women every year.

PMDD can be treated with antidepressants, birth control pills, or nutritional supplements. Diet and lifestyle changes, such as reducing caffeine and alcohol, getting enough sleep and exercise, and practicing relaxations techniques, can help. 

Premenstrual syndrome (PMS) is similar to PMDD in that symptoms occur seven to 10 days before a woman’s period begins. However, PMS involves fewer and less severe symptoms than PMDD.


Disruptive Mood Dysregulation Disorder

Disruptive mood dysregulation disorder is a condition that occurs in children and youth ages 6 to 18. It involves a chronic and severe irritability resulting in severe and frequent temper outbursts. The temper outbursts can be verbal or can involve behavior such as physical aggression toward people or property. These outbursts are significantly out of proportion to the situation and are not consistent with the child’s developmental age. They must occur frequently (three or more times per week on average) and typically in response to frustration. In between the outbursts, the child’s mood is persistently irritable or angry most of the day, nearly every day. This mood is noticeable by others, such as parents, teachers, and peers.

In order for a diagnosis of disruptive mood dysregulation disorder to be made, symptoms must be present for at least one year in at least two settings (such as at home, at school, with peers) and the condition must begin before age 10.  Disruptive mood dysregulation disorder is much more common in males than females. It may occur along with other disorders, including major depressive, attention-deficit/hyperactivity, anxiety, and conduct disorders.

Disruptive mood dysregulation disorder can have a significant impact on the child’s ability to function and a significant impact on the family. Chronic, severe irritability and temper outbursts can disrupt family life, make it difficult for the child/youth to make or keep friendships, and cause difficulties at school.

Treatment typically involves psychotherapy (cognitive behavior therapy) and/or medications. 

Persistent Depressive Disorder

A person with persistent depressive disorder (previously referred to as dysthymic disorder) has a depressed mood for most of the day, for more days than not, for at least two years. In children and adolescents, the mood can be irritable or depressed, and must continue for at least one year.

In addition to depressed mood, symptoms include:

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

Persistent depressive disorder often begins in childhood, adolescence, or early adulthood and affects an estimated 0.5% of adults in the United States every year. Individuals with persistent depressive disorder often describe their mood as sad or “down in the dumps.” Because these symptoms have become a part of the individual’s day-to-day experience, they may not seek help, just assuming that “I’ve always been this way.”

The symptoms cause significant distress or difficulty in work, social activities, or other important areas of functioning. While the impact of persistent depressive disorder on work, relationships and daily life can vary widely, its effects can be as great as or greater than those of major depressive disorder.

A major depressive episode may precede the onset of persistent depressive disorder but may also arise during (and be superimposed on) a previous diagnosis of persistent depressive disorder.

References

Physician Review By:

Felix Torres, M.D., MBA, DFAPA
October 2022

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