What is major depression?

The normal human emotion we sometimes call “depression” is a common response to a loss, failure or disappointment. Major depression is different. It is a serious emotional and biological disease that affects one’s thoughts, feelings, behavior, mood and physical health. Depression is a life-long condition in which periods of wellness alternate with recurrences of illness and may require long-term treatment to keep symptoms from returning, just like any other chronic medical illness.

All age groups and all racial, ethnic and socioeconomic groups can experience major depression. Some individuals may only have one episode of depression in a lifetime, but often people have recurrent episodes. If untreated, episodes commonly last anywhere from a few months to many years. An estimated 25 million American adults are affected by major depression in a given year, but only one-half ever receive treatment.

What are the symptoms of major depression and how is it diagnosed?

Depression can be difficult to detect from the outside, but for those who experience major depression, it is disruptive in a multitude of ways. It usually causes significant changes in how a person functions in many of the following areas:

Changes in sleep. Some people experience difficulty in falling asleep, waking up during the night or awakening earlier than desired. Other people sleep excessively or much longer than they used to.
Changes in appetite. Weight gain or weight loss demonstrates changes in eating habits and appetite during episodes of depression.
Poor concentration. The inability to concentrate and/or make decisions is a serious aspect of depression. During severe depression, some people find following the thread of a simple newspaper article to be extremely difficult, or making major decisions often impossible.
Loss of energy. The loss of energy and fatigue often affects people living with depression. Mental speed and activity are usually reduced, as is the ability to perform normal daily routines.
Lack of interest. During depression, people feel sad and lose interest in usual activities.
Low self-esteem. During periods of depression, people dwell on memories of losses or failures and feel excessive guilt and helplessness.
Hopelessness or guilt. The symptoms of depression often produce a strong feeling of hopelessness, or a belief that nothing will ever improve. These feelings can lead to thoughts of suicide.
Movement changes. People may literally look “slowed down” or overly activated and agitated.

Mental healthcare professionals use the criteria for depression in the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) to develop a diagnosis.

There is a strong possibility that a depressive episode can be a part of bipolar disorder. Having a physician make the right distinction between unipolar major depression and bipolar depression is critical because treatments for these two depressive disorders differ.

What treatments are available?

There are three well-established types of treatment for major depression:

Medications. Medications often effectively control the serious symptoms of depression. It often takes two to four weeks for antidepressant medications to have their full effect.
Psychotherapy. Several types of psychotherapy have been shown to be effective for depression, including cognitive behavioral therapy (CBT) and interpersonal therapy (IPT). Support groups offer opportunities to share frustrations and successes, referrals to specialists and community resources, and information about what works best when trying to recover. Research has shown that mild to moderate depression can often be treated successfully with either medication or psychotherapy alone but that both together are often more helpful. Severe depression appears more likely to respond to a combination of medication and psychotherapy.
Electroconvulsive therapy (ECT). ECT is a highly effective treatment for select severe depression episodes and for severe depression with psychosis. When medication and psychotherapy are not effective in treating severe symptoms (e.g., acute psychosis or thoughts of suicide) or if a person cannot take antidepressants, ECT may be considered. Memory problems can follow ECT treatments, so a careful risk-benefit assessment needs to be made for this intervention.
Other forms of treatment that may be helpful, either combined with the more traditional treatments or alone, include transcranial magnetic stimulation (TMS), aerobic exercise, and complementary and alternative medicine.
As devastating as this disease may be, it is very treatable in most people. Today the availability of treatment and understanding of depression has lessened the barriers that can prevent early detection, diagnosis and decision to seek treatment.
Reviewed by Ken Duckworth, M.D., April 2013