What is bipolar disorder?

Bipolar disorder, also called "manic-depressive" disease, is a mental illness that causes people to have high and low moods. People with this illness have periods of feeling overly happy and joyful (or irritable) or of feeling very sad or feeling normal. Because of the highs and the lows – or two poles of mood – the condition is referred to as "bipolar” disorder. However, patients’ moods may not necessarily follow a cyclic pattern, and sometimes the highs and lows can be experienced at the same time (mixed state). The hallmark of bipolar illness is the occurrence of the manic episode. In fact, by definition, to meet the criteria for bipolar disorder, patients must have at least one manic episode in their lifetime with or without ever experiencing a depressive episode.

The word “hypomania” or “manic” describes the periods when the person feels overly excited and confident. These feelings can quickly turn to confusion, irritability, anger, and even rage. The word “depressive” describes the periods when the person feels very sad or depressed. Because the symptoms are similar, sometimes people with bipolar depression are incorrectly diagnosed as having major depression. This is why it is especially important to screen for mania.

Most individuals with bipolar disorder spend three times the amount of time in depressed phases than in manic phases.

Who experiences bipolar disorder?

Bipolar disorder usually begins in older teens and young adults, with at least half of all cases appearing before age 25. Children and adolescents, however, can develop this disease in more severe forms and often in combination with attention deficit hyperactivity disorder (ADHD). Some studies have indicated that bipolar depression is genetically inherited, occurring more commonly within families.

While bipolar disorder occurs equally in women and men, women are more likely to meet criteria for bipolar II disorder. (With bipolar II, patients experience both depressive and hypomanic episodes, but do not experience the severe manic episodes seen in bipolar I.) Women with bipolar disorder may switch moods more quickly – this is called "rapid cycling." Varying levels of sex hormones and activity of the thyroid gland in the neck, together with the tendency to be prescribed antidepressants, may contribute to the more rapid cycling seen in women. Women may also experience more periods of depression than men.

An estimated 60 percent of all people with bipolar disorder have drug or alcohol dependence. It has also been shown to occur frequently in people with seasonal depression and certain anxiety disorders, like post-traumatic stress disorder (PTSD).

What causes bipolar disorder?

A definite cause for any type of depression is difficult to determine but include:

  • Genetics
  • Changes in the brain
  • Environmental factors like stress and major life changes

More research is being done to determine the relationship that these factors have in bipolar disorder, how they may help prevent its onset, and what role they may play in its treatment.

What are the symptoms of bipolar disorder?

The changing mood states do not always follow a set pattern, and depression does not always follow manic phases. A person may also experience the same mood state several times before experiencing the opposite mood. Mood changes can happen over a period of weeks, months, and sometimes even years.

An important aspect of the mood changes are that they are a departure from the person’s regular self and that the mood change is sustained for a long period of time. It may be many days or weeks in the case of mania and many weeks or months in the case of depression. Shorter periods of mania or depression may be an indicator of more severe episodes in the future but are usually not enough to diagnose a person with bipolar disorder.

The severity of the depressive and manic phases can differ from person to person and in the same person at different times. Symptoms of mania (“the highs”) include:

  • Excessive happiness, hopefulness, and excitement
  • Sudden changes from being joyful to being irritable, angry, and hostile
  • Restlessness
  • Rapid speech and poor concentration
  • Increased energy and less need for sleep
  • High sex drive
  • Tendency to make grand and unattainable plans
  • Tendency to show poor judgment, such as deciding to quit a job
  • Drug and alcohol abuse
  • Increased impulsivity

Some patients can become psychotic, seeing and hearing things that aren't there and holding false beliefs from which they cannot be swayed. In some instances they see themselves as having superhuman skills and powers, or think they are god-like.

The symptoms of bipolar depression are the same as those of major depression and include:

  • Sadness
  • Loss of energy
  • Feelings of hopelessness or worthlessness
  • Loss of enjoyment from things that were once pleasurable
  • Difficulty concentrating
  • Uncontrollable crying
  • Difficulty making decisions
  • Irritability
  • Increased need for sleep
  • Insomnia or excessive sleep
  • A change in appetite causing weight loss or gain
  • Thoughts of death or suicide
  • Attempting suicide

Patients with depression can also become psychotic and hear things or have delusions.

Last reviewed by a Cleveland Clinic medical professional on 01/27/2018.


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