What is Bipolar Disorder?

By Sarabeth Lowe, MPH

Ms. Lowe is a Communication Specialist at the University of Delaware Disaster Research Center.

Mood and emotions play important roles in our daily lives. We all experience periods of positivity and energy interspersed with bouts of sadness or irritability. For people with bipolar disorder, however, these fluctuations in mood are more than typical ups and downs. Both extremes are so intense and unpredictable that they disrupt day-to-day life and can have serious social, financial, and mental and physical health consequences.^1–7

What Is bipolar disorder?

Bipolar disorder is a mental health condition that causes intense mood swings.^4–10 These periodic, intense emotional states, which can last from days to weeks, are called mood episodes. They are categorized as manic/hypomanic episodes, where a person feels “up” (ie, high-spirited, irritable, or energized) or depressive episodes, where a person feels “down” (ie, sad, apathetic, numb, or despairing).^6,7 People can also experience mixed episodes, where manic and depressive symptoms occur together. Contrary to how the term is sometimes used in conversation, this diagnosis does not describe someone who is highly emotional; it refers to someone who experiences these extended periods of mood and energy that are excessively high or excessively low, with normal periods in between.⁴

Bipolar disorder typically begins in adolescence or early adulthood. It is estimated to affect 2.8% of adults in the United States, with men and women equally affected.¹¹ The exact causes of this disorder are unclear, but research shows that biological and environmental factors play a role.⁶ Genetics, trauma events or acute stress, and brain structure and function are thought to be contributing risk factors.^2–9,11,12

Diagnoses: A double-edged sword

The latest version of the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) is the American Psychiatric Association’s professional reference book on mental health and conditions. It specifies 3 main bipolar diagnoses, which are based on the type, duration, and severity of mood episodes.^{3–6,8–10,12–16} 

Bipolar I disorder. Bipolar I disorder is characterized by 1 or more episodes of mania that last at least 7 days or when manic symptoms are so severe that hospital care is needed. Most people diagnosed with bipolar I disorder will have episodes of both mania and depression, though an episode of depression is not necessary for a diagnosis. Mixed episodes and rapid cycling—experiencing 4 or more episodes of mania or depression within a year—are also possible.^{2,4–6,12,14–16} 

Bipolar II disorder. Bipolar II disorder is defined by a pattern of depressive and hypomanic episodes, a less severe and more brief form of mania that doesn’t include psychotic episodes.^{4–6,11,12,14–16} People with this subset never experience a “full” manic episode and often spend extended periods in a persistent, low-grade depressive state. Notably, bipolar II disorder is not a “lesser” form of the condition; it is a separate diagnosis.^4,10,17 

Cyclothymia. Cyclothymia is a milder form of bipolar disorder involving many “mood swings,” with hypomania and depressive symptoms that occur frequently but are not intense enough or do not last long enough to qualify as hypomanic or depressive episodes.^{2,4–10,15,16}

Diagnoses of “specified” and “unspecified” bipolar and related disorders are given when a person does not meet the criteria for bipolar I disorder, bipolar II disorder, or cyclothymia but has still experienced periods of clinically significant abnormal mood elevation.^2,5,10,12,18

Specifying these subdiagnostic categories is important because they help mental health practitioners provide a standardized and more dimensional way to assess symptoms and their severity, ensuring that people receive the most appropriate and effective treatment.^19,20 However, many experts say that this dichotomous perspective (ie, you have bipolar disorder or you don’t—there is no middle ground) fails to capture the wide spectrum of bipolar experiences. This can lead to misdiagnoses, underdiagnoses, ineffective treatment, and delayed care. A growing number of researchers, practitioners, and clinicians argue that having a spectrum-based approach to diagnosing bipolar disorder would capture this nuance.^8,10,19–24

Signs and Symptoms

Symptoms of bipolar disorder fall into 2 categories, mania and depression, and can include:^{2–7,11,14–16,24} 

Symptoms of a manic episode:

• Feeling very up, high, elated, extremely irritable, or touchy
• Feeling jumpy or wired, or being more active than usual
• Racing thoughts
• Decreased need for sleep
• Talking fast about a lot of different things (“flight of ideas”)
• Excessive appetite for food, drinking, sex, or other pleasurable activities
• Feeling able to do many things at once without getting tired
• Feeling unusually important, talented, or powerful

Symptoms of a major depressive episode: 

• Feeling very down, sad, or anxious
• Feeling slowed down or restless
• Trouble concentrating or making decisions
• Trouble falling asleep, waking up too early, or sleeping too much
• Talking very slowly, feeling unable to find anything to say, or forgetting a lot
• Lack of interest in almost all activities
• Unable to do even simple things
• Feeling hopeless or worthless, or thinking about death or suicide

Overlapping symptoms: 

Difficulty maintaining work responsibilities, social activities, or relationships

However, no case of bipolar disorder looks exactly the same. Changing mood states don’t always follow a set pattern, and symptoms and their severity can vary.^2,14 A person with bipolar disorder can have distinct manic or depressed states. They also may experience the same mood state several times with periods of euthymia, a neutral space between manic and depressive episodes often associated with a reduction in symptoms, in between.^14,25–27 People can also have extended periods, even years, without symptoms or experience both extremes simultaneously or in rapid sequence.^{2–7,11,12,14–16,21} Still, bipolar disorder is a chronic condition that can be treated and managed in several ways.

Treatment and Outcomes

Just as the symptoms of bipolar disorder look different from person to person, the long-term path of mood disorders also varies. Some people’s symptoms might improve over time, while others’ might worsen. Because it is a chronic illness with often recurring mood episodes, ongoing preventive treatment is recommended.^6,29 Some patients might get well without medication, but that is not possible for everyone, especially for those with more severe forms of bipolar disorder. Medication, particularly mood stabilizers and antipsychotics, is often the mainstay of treatment, with the benefits often outweighing the risks for most patients.^2,28–33 Some clinicians might add antidepressants to the treatment regimen, but they tend to be avoided in bipolar I disorder because they can trigger manic episodes in some patients.³³

Without adequate treatment, mood episodes can become more frequent over time.² Successful treatment and management of bipolar disorder often combines several approaches, including psychotherapy (eg, cognitive behavioral therapy and family-focused therapy), self-management strategies (ie, education, support groups, and recognition of an episode’s early symptoms), and complementary health approaches (eg, sticking to a regular sleep schedule, reducing alcohol consumption, and meditation; these strategies can help support, but cannot replace, clinical treatment).^{4,5,8,10,28–33}

Although there is no known cure for bipolar disorder, recovery is possible. With the right combination of medication, support, and lifestyle changes, the vast majority of people go on to live to productive, fulfilling lives.

Sources

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