The essential feature of bipolar disorder II is a clinical course characterized by the appearance of one or more major depressive episodes accompanied by at least one hypomanic episode. Episodes of mood disorder substance induced (due to the direct physiological effects of a medication, other somatic treatments for depression, drugs or exposure to toxic) or mood disorders due to medical condition are not considered valid for the diagnosis of bipolar II disorder.
In addition, the episodes must not better accounted for by Schizoaffective Disorder and are not to be superimposed on schizophrenia, schizophreniform disorder, delusional disorder or psychotic disorder not otherwise specified.
The symptoms must cause clinically significant distress or impairment in social, occupational or other important areas of functioning. In some cases, hypomanic episodes do not cause damage themselves. Instead, damage can result from major depressive episodes or a chronic pattern of unpredictable mood episodes and interpersonal or occupational activity fluctuations.
Individuals with a bipolar disorder II may not consider pathological hypomanic episodes, although others are affected by changing behavior. Often the subjects, especially when they are in full major depressive episode, can not remember periods of hypomania, unless via friends or relatives. The information from others is often crucial to establishing the diagnosis of bipolar disorder II.
Descriptive features and mental disorders. Completed suicide (usually during major depressive episodes) is a significant risk, as occurs in 10-15% of people with bipolar disorder II. School absences, school or job failure and divorce can be associated with bipolar II disorder. The mental disorders include abuse or substance dependence, anorexia nervosa, bulimia nervosa, attention deficit disorder with hyperactivity, panic disorder, social phobia and borderline personality disorder.
Symptoms Specific Gender
Bipolar disorder II appears more often in women than in men. Women with bipolar II disorder seem to have a higher risk of further episodes in the immediate postpartum period.
Prevalence
Studies in the general population suggest that the prevalence of bipolar II disorder is approximately 0.5%.
Approximately 60-70% of hypomanic episodes in bipolar II disorder occur immediately before or after a major depressive episode. Hypomanic episodes often precede or follow major depressive episodes with a characteristic pattern in each individual. The number of episodes throughout life (both hypomanic episodes and major depressive episodes) tends to be higher in bipolar disorder II than in major depressive disorder relapse. The interval between episodes tends to shorten with increasing age.
