Bipolar II disorder
Bipolar II disorder 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.
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, atypical antipsychotics, as well as psychotherapy. Antidepressant use in bipolar disorder is controversial, with some studies finding benefit, while others find risks of switching to hypomania or worsening of rapid cycling.
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 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.
Causes
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.Signs and symptoms
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.Hypomania
Hypomania is the signature characteristic of BP-II, defined by an experience of elevated mood. A patient's mood is typically cheerful, enthusiastic, euphoric, or irritable. In addition, they can present with symptoms of inflated self-esteem or grandiosity, decreased need for sleep, talkativeness or pressured speech, flight of ideas or rapid cycling of thoughts, distractibility, increased goal-directed activity, psychomotor agitation, and/or excessive involvement in activities that have a high potential for painful consequencesHypomania is distinct from mania. During a typical hypomanic episode, patients may present as upbeat, may show signs of poor judgment or display signs of increased energy despite lack of sleep, but do not meet the full criteria for an acute manic episode. Patients may display elevated confidence, but do not express delusional thoughts as in mania. They can experience increase in goal-directed activity and creativity, but do not reach the severity of aimlessness and disorganization. Speech may be rapid, but interruptible. Patients with hypomania never present with psychotic symptoms and do not reach the severity to require psychiatric hospitalization.
For these reasons, hypomania commonly goes unnoticed. Individuals often will only seek treatment during a depressive episode, and their history of hypomania may go undiagnosed. Although hypomania may increase functioning, episodes require treatment as they may indicate increasing instability and can precipitate a depressive episode.
Depressive episodes
It is during depressive episodes that BP-II patients often seek help. Symptoms may be syndromal or subsyndromal.Depressive episodes in BP-II can present similarly to those experienced in unipolar depressive disorders. Patients characteristically experience a depressed mood and may describe themselves as feeling sad, gloomy, down in the dumps, or hopeless, for most of the day, nearly every day. In children, this can present with an irritable mood. Most patients report significant fatigue, loss of energy, or tiredness. Patients or their family members may note diminished interest in usual activities such as sex, hobbies, or daily routines. Many patients report a change in appetite along with associated weight change. Sleep disturbances may be present, and can manifest as problems falling or staying asleep, frequent awakenings, excessive sleep, or difficulties getting up in the morning.
Around half of depressed patients develop changes in psychomotor activity, described as slowness in thinking, speaking, or movement. Conversely, they may also present with agitation, with inability to sit still or wringing their hands. Changes in posture, speech, facial expression, and grooming can be observed. Other signs and symptoms include changes in posture and facial expression, slowed speech, poor hygiene, unkempt appearance, feelings of guilt, shame, or helplessness, diminished ability to concentrate, nihilistic thoughts, and suicidal ideation.
Many experts in the field have attempted to find reliable differences between BP-II depressive episodes and episodes of major depressive disorder, but the data is inconsistent. However, some clinicians report that patients who came in with a depressive episode, but were later diagnosed as having bipolar disorder often presented with hypersomnia, increased appetite, psychomotor retardation, and a history of antidepressant-induced hypomania. Evidence also suggests that unlike MDD depressive episodes, BP-II depressive episodes tend to include symptoms more commonly associated with atypical depression, such as overeating or oversleeping. Other factors that can distinguish BP-II from MDD are age of onset, which is lower for BP, the frequency of recurrence, which is greater for BP-II, and bipolar disorder family history.
Mood episodes with mixed features
A mixed episode is defined by the presence of a hypomanic or depressive episode that is accompanied by symptoms of the opposite polarity. This is commonly referred to as a mood episode with mixed features, but can also be referred to as mixed episodes or mixed states. For example, a patient with depression with mixed features may have a depressed mood, but has simultaneous symptoms of rapid speech, increased energy, and flight of ideas. Conversely, a patient with hypomania with mixed features will present with the full criteria for a hypomanic episode, but with concurrent symptoms of decreased appetite, loss of interest, and low energy.Episodes with mixed features can last up to several months. They occur more frequently in patients with an earlier onset of bipolar disorder, are associated with higher frequency of episodes, and are associated with a greater risk of substance use, anxiety disorders, and suicidality. In addition, they are associated with increased treatment resistance compared to non-mixed episodes.
Psychosis
An estimated 20% of people with bipolar II disorder have experienced psychosis. Symptoms of psychosis include delusions, hallucinations, or both. Delusions are more common than hallucinations in bipolar disorder. In general, having psychotic episodes means the illness is more severe. People with psychosis have poor insight and more agitation, anxiety, and hostility.In contrast to bipolar II, in bipolar I, more than 50% of people have experienced psychosis. Psychosis is more common during manic episodes than depressive episodes, so psychotic symptoms are more common in bipolar type I compared to bipolar type II.