WEDNESDAY, May 9, 2007 (HealthDay News) -- Bipolar spectrum disorder may be under-recognized, and many people with the illness do not receive proper treatment, new U.S. research suggests.
The study, published in the May issue of the journal Archives of General Psychiatry, analyzed data from a survey of mental disorders among almost 9,300 Americans, ages 18 and older.
It identified prevalence rates for three subtypes of bipolar spectrum disorder.
These are:
- Bipolar I. This is considered the classic form of the illness, in which patients experience recurrent episodes of mania and depression.
- Bipolar II. Patients experience a milder form of mania called hypomania that alternates with depressive episodes.
- Bipolar disorder not otherwise specified (BD-NOS), also called subthreshold bipolar disorder. Patients have manic and depressive symptoms but don't meet strict criteria for any specific type of bipolar disorder noted in the Diagnostic and Statistical Manual for Mental Disorders.
Bipolar I and bipolar II each occur in about one percent of the U.S. population, while BD-NOS occurs in about 2.4 percent of the population, the study said. The researchers said their findings support previous studies that suggested that bipolar disorder may be better characterized as a spectrum disorder.
The study found that 89 percent to 95 percent of patients with bipolar I or bipolar II, and 69 percent of those with BD-NOS, were receiving some kind of treatment. However, many of them were receiving treatment for co-existing psychiatric conditions -- such as anxiety, depression or substance abuse -- rather than for bipolar disorder.
Many of the patients were receiving treatments considered inappropriate for bipolar disorder, such as taking an antidepressant or other psychotropic medication in the absence of a mood-stabilizing medication such as lithium, valproate, or carbamazepine, the study authors said.
They noted that only about 40 percent of bipolar disorder patients were receiving appropriate mood stabilizer, anticonvulsant or antipsychotic medication.
"Such a high rate of inappropriate mediation use among people with bipolar spectrum disorder is a concern. It is potentially dangerous because use of an antidepressant without the benefit of a mood stabilizer may actually worsen the condition," study author Kathleen Merikangas, of the National Institute of Mental Health, said in a prepared statement.
More information
The American Academy of Family Physicians has more about bipolar disorder.
