Etiology of Bipolar Disorder

Bipolar Disorder patients have manic and depressive episodes frequently in their lives. These episodes can affect people from the early teens until death. Bipolar Disorder comes with a number of treatment plans and medications, but a singular cause has yet to be determined. Many theories exist on the etiology of Bipolar Disorder.

Bipolar Subtypes

• Although Bipolar Disorder is characterized by mood swings, there are several subtypes. A Bipolar 1 diagnosis involves both manic and depressive mood episodes that last from several weeks to several months apiece. In between the mood swings are a few months of a "balanced" or normal mood. Bipolar 2 patients have hypomanic episodes and more chronic depressive episodes that tend to last longer. Rapid Cycling Bipolar Disorder characterizes shorter periods of mood swings with at least four cycles within a year. Some of these swings can take place even within 24 hours.

Dopamine

• The neurotransmitter theory suggests that Bipolar Disorder is largely a result of chemical imbalances in the brain. Neurotransmitters are responsible for communicating information between the various brain functions. Several studies have claimed that dopamine, which helps control pleasure feelings, are at significantly higher levels in bipolar patients during periods of mania. They are also lower than normal during depressive episodes. However, the Brain Explorer website (see References) states that these level differences may exist, but it may not be the cause. Rather, cell functions during these episodes should be explored.

Genetic Predisposition

• Genetic predisposition to Bipolar Disorder is another explored etiology. Recent Swedish studies have shown that schizophrenia and Bipolar Disorder will run in families that have either disease. Genetic Epidiomologist Paul Lichtenstein led a study published in a January 2009 issue of The Lancet that focused on psychiatric records. By studying over 30 years of psychiatric hospital discharge records, he found that a person had 6 times the chance of having Bipolar Disorder if either parent had it. The heritability Bipolar Disorder, according to the study, is 59 percent.

Borna Virus Disease

• The Borna Virus Disease affects the nervous system of humans and animals. In fact, the Borna Virus can be transmitted between both. Symptoms associated with the Borna Virus in humans include those that resemble manic depression, leading researchers to think that it may also be the cause of Bipolar Disorder. The AccessExcellence.org website reports that German researchers found that 20 percent of their patients with mood disorders also had Borna Virus disease antibodies in their systems.

Medications and Mania

• Some antidepressants, according to some researchers, may also cause mania. Some antidepressants work by increasing levels of serotonin, a neurotransmitter that helps regulate pleasurable moods. Serotonin levels can be significantly decreased in depressed patients. A Psych Education Organization website (see Resource) report listed various controversies and studies of this possible phenomenon.