History, Diagnosis, and Outcomes
The diagnostic precursor to bipolar illness was manic-depressive illness, which was understood to be an episodic disorder, characterized by alternating bouts of depression and mania. This was understood to be a rare disorder, such that were only about 12,750 people in the U.S. hospitalized with this diagnosis in 1955.
The “bipolar” diagnosis first appeared in the third edition of the American Psychiatric Association’s Diagnostic and Statistical Manual. It is defined by the presence of depressive episodes which alternate with manic or hypomanic episodes.
The bipolar diagnosis is split into two types. The main difference is that bipolar I requires manic experiences. Bipolar II requires hypomania instead, and is considered less severe. A diagnosis of bipolar II may be made even though a person has not required hospitalization (which had been the case for a diagnosis of manic-depressive disorder).
There are many apparent pathways to bipolar. Use of antidepressants to treat a depressive episode increases the risk that a person will experience a manic or hypomanic episode and thus convert to a bipolar diagnosis. Similarly, the use of marijuana and other psychoactive drugs increases the risk that a person will end up diagnosed with bipolar disorder.
According to the medical model promoted by the American Psychiatric Association, bipolar is a chronic brain illness, although there is no accepted theory of how it develops in the brain, or what the underlying pathology may be.
Bipolar disorder is usually treated with a variety of drugs, including lithium, antiepileptic drugs such as valproate, antidepressants, and neuroleptic tranquilizers (sometimes called “antipsychotics”). Outcomes with this mode of treatment are understood to be poor, with researchers acknowledging that the course of bipolar disorder has worsened in the pharmacological era. The disorder now runs a much more chronic course than it did before the arrival of lithium and the practice of treating patients with two or more drugs at once.