Overview of Mood Disorders

ByWilliam Coryell, MD, University of Iowa Carver College of Medicine
Reviewed/Revised Oct 2023
VIEW PROFESSIONAL VERSION

Mood disorders are mental health conditions that involve long periods of excessive sadness (depression), excessive elation (mania), or both. Depression and mania represent the 2 emotional extremes of mood disorders.

Sadness and happiness are part of everyday life and are different from severe emotional issues that are diagnosed as the depression and mania that are experienced by people with mood disorders.

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Sadness is a natural response to loss, defeat, disappointment, trauma, or catastrophe. Grief or bereavement is the most common of the normal reactions to a loss or separation, such as the death of a loved one, divorce, or romantic disappointment. Usually, bereavement and loss do not cause persistent, incapacitating depression except in people predisposed to mood disorders. In some people, loss of a loved one causes more persistent and disabling depression, which has been termed prolonged grief disorder.

Did You Know...

  • Many people who visit a doctor say they feel depressed, but only a few have depression that is severe enough to be diagnosed as a mood disorder.

Happiness, elation, or joy are emotions people experience when they are feeling positive about something. Mania is an abnormal mood state that may feel like happiness to a person who has a mood disorder and is in the middle of a manic episode. It is typically associated with periods of excessive excitement, hyperactivity, and impulsivity. During a manic episode, individuals may experience a decreased need for sleep, inflated self-esteem or grandiosity, racing thoughts, rapid speech, distractibility, and engagement in risky behaviors. Mania is significantly different from a normal range of emotions and can lead to impairment in functioning and relationships.

A mood disorder is diagnosed when sadness or elation is more intense than usual, is accompanied by certain other symptoms, and impairs the ability to function physically, socially, and at work.

When only depression occurs, the medical term is unipolar disorder, which can describe several disorders:

  • Major depressive disorder

  • Persistent depressive disorder

  • Premenstrual dysphoric disorder

  • Substance/medication-induced depressive disorder

Bipolar disorders, which involve episodes of depression alternating with episodes of mania or hypomania (a less severe form of mania), are another category of mood disorder. Mania without depression (called unipolar mania) is very rare.

About 30% of people report depression as one of their symptoms when they see their doctor. But fewer than 10% actually have severe depression. Nearly 4% of the U.S. population have a bipolar disorder.

Mood disorders in children and adolescents can also occur.

Having a mood disorder, particularly one that involves depression, increases the risk of other issues, such as inability to do daily activities and maintain relationships, loss of appetite, extreme anxiety, and alcohol use disorder. The highest concern is that as many as 15% of people with untreated depression end their life by suicide.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  1. Mental Health America (MHA): Community-based nonprofit organization that promotes mental health as a critical part of overall wellness and provides educational materials and information on public policy

  2. National Alliance on Mental Illness (NAMI): Largest grassroots mental health organization in the United States dedicated to improving the lives of people living with mental illness

  3. National Institutes of Mental Health (NIMH): General information on many aspects of mental illness, including research, legislation, and outreach

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