Bipolar Disorder, previously referred to as manic depression, is a frequent cause of disability in young people. Those suffering from Bipolar Disorder experience depression almost identical to that associated with unipolar depression. But in addition with Bipolar Disorder there are episodes of mania or the less severe hypomania.
In Bipolar 1 Disorder both mania and hypomania may occur. In Bipolar 2 Disorder only hypomanic episodes occur along with depression. In both types of Bipolar Disorder, depression occurs much more frequently than the manic/hypomanic attacks.
A specific list of criteria exist that must be met to establish the diagnosis of Bipolar Disorder. More often than not, an individual patient fails to meet all of the features necessary for the disorder. These individuals are designated as suffering the subsyndromal disorder - a condition about 3 times more frequent than the canonical disorder according to the American Psychiatric Association.
A lag of 10 years from onset of symptoms until diagnosis is not uncommon.
Manifestations of manic episodes include overconfidence, grandiosity, talkativeness, irritability, disinhibition, decreased need for sleep and a highly elated mood. Not uncommonly psychotic symptoms may supervene. These include hallucinations and delusions and may require hospitalization.
Hypomania is associated with less severe symptoms that may be interpreted by the individual as positive in nature and helpful with work or social activities.
Usually episodes of mania and depression remain distinct but at times they occur simultaneously. So-called mixed episodes carry a worse prognosis and further increase the risk of suicide even beyond the typically elevated rate associated with Bipolar Disorder in general. Rapid cycling refers to at least 4 discrete episodes of depression and mania within the prior 12 months and again signals more severe disease.
The lifetime prevalence of Bipolar Disorder in all of its forms is nearly 2.5% of the population with some estimates rising to 4%. In Bipolar 1 Disorder the sex incidence appears equal. In Bipolar 2 Disorder women predominate. Agoraphobia frequently coexists with Bipolar Disorder.