Test Your Knowledge

There are many different types of mood disorders, most of which involve some episodes of depression.  To meet established criteria for a depressive mood disorder, episodes must not be related to a general health condition or the use of a substance. Depressive mood disorders include:

• Major depression. One or more major depressive episodes occur in a patient with no history of any type of manic episodes.
  
  
• Dysthymia. Depression that is not severe enough to fulfill the criteria for a major depressive episode and lasts for at least two years. The patient must not have a history of manic episodes.
  
  
• Seasonal affective disorder (SAD). Occurs when people become depressed during a particular season (most often the winter).  
  
  
• Postpartum depression (PPD). Type of depression that follows childbirth. Historically, PPD has been diagnosed solely in women, but researchers now believe that men may be affected by the condition as well.
   
• Depressive disorder, not otherwise specified (NOS). A patient with depressive symptoms that do not meet the criteria for any specific depressive disorder may receive this diagnosis.

Bipolar disorder is a mood disorder that includes at least one episode of abnormally high mood, which cannot be attributed to a general medical condition or the use of a substance. Types of bipolar disorder include:

• Bipolar I disorder. The occurrence of at least one manic or mixed episode (includes both manic and depressive elements at the same time), with or without episodes of major depression.
  
  
• Bipolar II disorder. The occurrence of at least one episode of major depression and one episode of hypomania (a milder form of mania). The patient must have never experienced a manic or mixed episode. This disorder may develop into bipolar I disorder if a manic episode occurs.
  
  
• Cyclothymia. Repeated mood swings with hypomania and lows in mood that do not meet the criteria for major depressive episodes. This disorder is chronic and lasts for at least two years. It may develop into bipolar I disorder if a manic episode occurs or into bipolar II disorder if a major depressive episode occurs.
  
  
• Bipolar disorder, NOS. Symptoms of bipolar disorder that do not meet the criteria for any other bipolar diagnosis. These may be more common in early onset bipolar disorder.

Other mood disorders include:

• Mood disorder due to a general medical condition. Abnormal highs or lows in mood caused by a physical illness. Conditions that can lead to a mood disorder include endocrine disorders (e.g., thyroid disorders), neurological conditions (e.g., Alzheimer’s disease, epilepsy, stroke), brain tumors and viral infections.
  
  
• Substance-induced mood disorder. Abnormal highs or lows in mood caused by the use of a substance, such as alcohol, illegal drugs or prescription medications (e.g., anti-anxiety drugs, corticosteroids).
  
  
• Mood disorder, NOS. Any alteration in mood that does not meet the criteria for the diagnosis of any other mood disorder.