Bipolar depression is also a form of affective disorder. It occurs episodically, i.e. alternating between phases of no symptoms and phases with clear signs of illness. However, in contrast to unipolar depression, bipolar depression (formerly known as “manic-depression”) is characterized by a fluctuation of one’s mood between two opposing poles. These emotional fluctuations go far beyond the usual level.
Affected individuals experience extreme highs during which they exhibit abnormally elevated or irritable mood, as well as a persistent increase in activity and performance for at least a week. Oftentimes, they will experience a decreased need for sleep, racing thoughts, are highly distractible and will exhibit risky and reckless behavior (e.g. acquiring large amounts of debt). A severe manic episode can even lead to delusional states (mostly delusions of grandeur) and hallucinations . These phases of extreme elation and activity alternate with extreme low phases that are symptomatically equivalent to an episode of major depression. Individuals suffering from bipolar disorder often describe their emotional state as going from the top of the world to down in the dumps. However, there are also mixed affective episodes in which manic and depressive symptoms do not alternate but occur simultaneously .
The mechanism underlying bipolar disorder are still not 100% clear. Similar to unipolar depression, it is assumed that both genetic and biological, as well as environmental influences and personality traits play a decisive role .
The probability of developing bipolar depression in one’s lifetime is about 3% and often manifests itself in adolescence and young adulthood. Unfortunately, on average, it takes 5 to 10 years after the first onset of symptoms for patients to be properly diagnosed and adequately treated .
Due to the severity of the symptoms, many affected individuals experience a serious impairment of their day to day level of functioning. However, if correctly diagnosed and with individual and appropriate therapy, most people suffering from bipolar disorder can regain their quality of life.