Bipolar disorder, previously called maniodepressive psychosis or manic depression. Experts classify it as one of the most severe chronic mental illnesses, lasting in varying intensity throughout life and negatively affecting both the private and professional spheres. Unemployment among people with bipolar disorder can be as high as 70%, and the risk of suicide is 10-20 times higher than in the general population [1] [2].

The term itself suggests that it is a mood disorder manifesting in two poles (from the word “bipolar”), namely depression and mania [6].

Mania, or manic episode or phase, is manifested as an extremely euphoric, sometimes irritable mood, increased activity, and decreased need of sleep. A person in mania may be more communicative, friendly; his thoughts and speech tends to be faster. Also, new ideas, financially challenging plans, or risky and promiscuous behavior may come up. Some of the most serious symptoms include the occurrence of psychotic symptoms, i.e. hallucinations or irrefutable beliefs (called delusions) or general exhaustion of the body. Because of these symptoms, more than half of people with acute manic symptoms are hospitalized. To diagnose mania, the symptoms must persist for at least seven days. The state of hypomania has similar manifestations but with less intensity and severity [3] [4] [5].

A depressive episode, on the other hand, manifests as a pessimistic mood, self-effacing thoughts, and a decrease in energy. Some people need to sleep more than usual, while others experience a reduction in sleep hours. In depression, there are also attention difficulties; normal daily activities are almost impossible to perform, and getting out of bed is demanding. Depression is often accompanied by anxiety, and sometimes psychotic symptoms can occur, for example, in the form of highly negative beliefs about oneself or one’s life. To be diagnosed with depression, symptoms must persist for at least 14 days [4] [5]. 

Bipolar disorder takes many forms. It may manifest itself by alternating mania and depression or mixed states, which include symptoms of both poles, and a state without symptoms, called remission. The course of the disease is different for everyone and can change throughout life [4] [6]. 

Dictionary:

Manic psychosis = manic depression = bipolar disorder 

Mixed state = occurrence of symptoms of mania and depression in the same period; in this state, there is a high risk of suicidal behavior

Episode = phase of illness; in bipolar disorder, we use the terms depressive/hypomanic/manic episode or phases

[1] Novick, D. M., Swartz, H. A., & Frank, E. (2010). Suicide attempts in bipolar I and bipolar II disorder: a review and meta‐analysis of the evidence. Bipolar disorders, 12(1), 1-9.

[2] Crump, C., Sundquist, K., Winkleby, M. A., & Sundquist, J. (2013). Comorbidities and Mortality in Bipolar Disorder: A Swedish National Cohort Study. JAMA Psychiatry, 70(9), 931–939. https://doi.org/10.1001/jamapsychiatry.2013.1394

[3]de Zelicourt, M., Dardennes, R., Verdoux, H., Gandhi, G., Khoshnood, B., Chomette, E., Papatheodorou, M.-L., Edgell, E. T., Even, C., & Fagnani, F. (2003). Frequency of Hospitalisations and Inpatient Care Costs of Manic Episodes: In Patients with Bipolar I Disorder in France. PharmacoEconomics, 21(15), 1081–1090. https://doi.org/10.2165/00019053-200321150-00002

[4] Vieta, E., Berk, M., Schulze, T. G., Carvalho, A. F., Suppes, T., Calabrese, J. R., Gao, K., Miskowiak, K. W., & Grande, I. (2018). Bipolar disorders. Nature Reviews Disease Primers, 4, 18008. https://doi.org/10.1038/nrdp.2018.8

[5] MKN-10. (2017). Mezinárodní statistická klasifikace nemocí a přidružených zdravotních problémů: desátá revize. Aktualizované vydání k 1.1.2018. (Roč. 2017). Praha: Ústav zdravotnických informací a statistiky ČR.

[6] Látalová, K. (2010). Bipolární afektivní porucha (Vyd. 1). Praha: Grada.