Major Depressive Disorder


Article written by P. Terwilliger, edited and reviewed by M. Williams, Ph.D.

Major Depressive Disorder and Unipolar Depression

What is Major Depressive Disorder?

Major Depressive Disorder, also called Clinical Depression, is a serious psychiatric illness that should not be confused with temporary sadness or "the blues." People use the term "depression" to mean many things, such as the sadness, despondency, and dejection. Major Depressive Disorder, on the other hand, is a clinical syndrome that includes symptoms of depression (as a mood), as well as physical symptoms such as fatigue, a loss of energy, and sleeping difficulties.

The opposite of depression is mania, where a person feels euphoric; symptoms of mania include feelings of physical and emotional well being, exaggerated self-esteem, pressured speech, and racing thoughts. People who have alternating bouts of depression and mania have Bipolar Disorder. People with only bouts of depression have Unipolar Depression.

Major depressive disorder is episodic

Major depressive disorder should be thought of as episodic. The minimum duration of unipolar disorder is 2 weeks, but it can last much longer. Most who have unipolar disorder will have at least two depressive episodes and one half will recover within 6 months while 40% of all who recover will relapse within a year. The ratio of unipolar to bipolar people is 5:1.

Major Depressive Disorder Symptoms

  • Depressed (sad) mood
  • Lack of pleasure or interest in activities
  • Sleep disturbance (sleeping too much or too little)
  • Weight loss
  • Loss of energy
  • Social withdrawal
  • Agitation or psychomotor retardation (moving very slowly)
  • Feelings of worthlessness or inappropriate guilt
  • Diminished concentration, or indecisiveness
  • Frequent thoughts of death or suicide
  • Thoughts about hurting self

What are the Symptoms of Major Depressive Disorder?

There are numerous symptoms of major depressive disorder including cognitive, somatic, and behavioral symptoms with a few others.

Cognitive symptoms occur in thoughts. Typical examples of cognitive symptoms are slowed thinking, poor concentration, and suicidal or morbid thoughts.

Somatic symptoms are those that result in physical problems, such as fatigue, insomnia, lethargy, aches and pains, changes in appetite and sleep patterns, anhedonia (loss of pleasure in life), and a loss of sexual desire.

Behavioral symptoms include psychomotor retardation, which is the slowing down of motor responses, and social withdrawal.

Emotional symptoms may include sadness, feelings of guilt, and anxiety (which two out of three patients experience).

Other possible symptoms of clinical depression are alcoholism, eating disorders, and other comorbid disorders (more than one disorder at once).

Types of Major Depressive Disorder

Depression may also exist in manic-depressive disorder or bipolar disorder.

Bipolar I disorder is a disorder where a person has experienced at least one manic episode

Bipolar II disorder is where a person has experienced at least one major depressive episode, at least one hypomanic episode, and no full blown manic episodes.

Unipolar mood disorder is where a person experiences only episodes of depression rather than episodes of depression and mania.

Causes of Major Depressive Disorder

There are many causes of major depressive disorder, including social events, personality type, biological factors that contribute and also raise the probability of relapse.

The biggest predictor of a future depressive episode is a history of depression in the past. Having another mental disorder puts one at a higher risk for depression as well. This is one reason it is important to seek treatment right away. Many times, though, it is the combination of biological, social, and psychological factors that create clinical depression in a person.

  • Social factors. Social difficulties, such as death, divorce, financial problems, and other stressful life events can trigger depression. Compounding stressful events can make depression even more likely.
  • Psychological factors. How a person interprets life events can be a major factor in the tendency to become depressed. Overly negative views of the self (low self esteem), and pessimism about the future can play an important role. The combination of anger and feelings of helplessness are often found at the root of depressive episodes. Hopelessness and lack of control may also contribute.
  • Biological factors. Genetics have been implicated as contributing factor in depression as the disorder tends to run in families. Hormones seem to play a role, and this is especially evident in disorders such as PMS or Premenstrual Dysphoric Disorder and Postpartum Depression.

Treatment for Major Depressive Disorder

There are many ways to treat major depressive disorder, and research has shown the most effective treatments are cognitive, interpersonal, or behavioral therapy, as well as antidepressant medication.

Cognitive therapy focuses on recognizing, challenging, and overcoming how one thinks of a situation. It helps the person to think about the situation differently.

Interpersonal therapy focuses on helping relationships.

Behavioral therapy focuses on changing behaviors, such as exercise to help the patient.

Antidepressant medication (such as Prozac) is medication that changes brain chemistry, and is often used with other forms of therapy.

Faith-based and self-help strategies can be helpful for people who are highly motivated.

Electroconvulsive therapy (ECT), also called "Shock Treatment," is a remedy of last resort for those with severe depression.

Major depressive disorder, or clinical depression, is a serious mental disorder that can seriously impair a person's life. Fortunately, there has been extensive research on this illness and there are many excellent treatments. As we learn more about this disorder future treatments will continue to become more effective.

Photo by John Nyboer

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