Bipolar II disorder

Bipolar II disorder (BP-II) is a mood disorder on the bipolar spectrum, characterized by at least one episode of hypomania and at least one episode of major depression. Diagnosis for BP-II requires that the individual must never have experienced a full manic episode. Otherwise, one manic episode meets the criteria for bipolar I disorder (BP-I).

Bipolar II Disorder is a mood disorder characterized by alternating periods of depression and hypomania, a less severe form of mania. Individuals with Bipolar II experience episodes of major depression, marked by symptoms like persistent sadness, fatigue, and loss of interest in activities, as well as episodes of hypomania, which involve elevated mood, increased energy, and impulsivity, but without the full-blown manic episodes seen in Bipolar I Disorder.

The disorder is often underdiagnosed because the hypomanic episodes may not be as disruptive as full mania. Bipolar II tends to be chronic and can significantly impact a person's social, professional, and emotional life. Though the causes are not fully understood, a combination of genetic, environmental, and neurobiological factors is believed to play a role.

Bipolar II is typically managed through a combination of medication (such as mood stabilizers and antidepressants) and psychotherapy. Early diagnosis and treatment can help mitigate the intensity and frequency of mood episodes. Hypomania is a sustained state of elevated or irritable mood that is less severe than mania yet may still significantly affect the quality of life and result in permanent consequences including reckless spending, damaged relationships and poor judgment. Unlike mania, hypomania cannot include psychosis. The hypomanic episodes associated with BP-II must last for at least four days.

Commonly, depressive episodes are more frequent and more intense than hypomanic episodes. Additionally, when compared to BP-I, type II presents more frequent depressive episodes and shorter intervals of well-being. The course of BP-II is more chronic and consists of more frequent cycling than the course of BP-I. Finally, BP-II is associated with a greater risk of suicidal thoughts and behaviors than BP-I or unipolar depression. BP-II is no less severe than BP-I, and types I and II present equally severe burdens.

BP-II is notoriously difficult to diagnose. Patients usually seek help when they are in a depressed state, or when their hypomanic symptoms manifest themselves in unwanted effects, such as high levels of anxiety, or the seeming inability to focus on tasks. Because many of the symptoms of hypomania are often mistaken for high-functioning behavior or simply attributed to personality, patients are typically not aware of their hypomanic symptoms. In addition, many people with BP-II have periods of normal affect. As a result, when patients seek help, they are very often unable to provide their doctor with all the information needed for an accurate assessment; these individuals are often misdiagnosed with unipolar depression. BP-II is more common than BP-I, while BP-II and major depressive disorder have about the same rate of diagnosis. Substance use disorders (which have high co-morbidity with BP-II) and periods of mixed depression may also make it more difficult to accurately identify BP-II. Despite the difficulties, it is important that BP-II individuals be correctly assessed so that they can receive the proper treatment. Antidepressant use, in the absence of mood stabilizers, is correlated with worsening BP-II symptoms.

Multiple factors contribute to the development of bipolar spectrum disorders, although there have been very few studies conducted to examine the possible causes of BP-II specifically. While no identifiable single dysfunctions in specific neurotransmitters have been found, preliminary data has shown that calcium signal transmission, the glutamatergic system, and hormonal regulation play a role in the pathophysiology of the disease. The cause of Bipolar disorder can be attributed to misfiring neurotransmitters that overstimulate the amygdala, which in turn causes the prefrontal cortex to stop working properly. The bipolar patient becomes overwhelmed with emotional stimulation with no way of understanding it, which can trigger mania and exacerbate the effects of depression.

Bipolar disorder is characterized by marked swings in mood, activity, and behavior. BP-II is characterized by periods of hypomania, which may occur before, after, or independently of a depressive episode.