Bipolar, or manic-depressive, disorders are frequent and severe mental illnesses associated with considerable morbidity and mortality. Epilepsy and bipolar disorder could probably share some aspects of pathophysiology because manic as well as depressive symptoms are seen in patients with seizures, and a number of antiepileptic drugs are effectively used in the acute and prophylactic treatment of bipolar disorder. Epidemiologic research suggests a dimensional composition of bipolar illness at the population level. Apart from the DSM-IV diagnostic features of bipolar I (mania and depression) and bipolar II (hypomania and depression), the concept of bipolar spectrum disorders comprises a range of bipolar conditions with less obvious manifestations with estimated lifetime prevalence rates ranging from 2.8 to 6.5%. Expanding the definition of bipolar II disorders shows that half of the patients currently diagnosed with a unipolar depressive episode could suffer from unrecognized bipolar II disorder, and about the same number of mild depressive patients could be minor bipolars. Research efforts to refine the diagnostic criteria of bipolar disorder aim at an earlier and complete recognition of the disease to provide appropriate pharmacological and nonpharmacological treatment early in the course of the illness to anticipate individual suffering, suicidal behavior, and increased socioeconomic costs for society. This article also discusses risk factors, comorbid conditions, course of illness, as well as the individual and socioeconomic impact of bipolar disorders.
Conclusions: The findings suggest reconceptualizing bipolar illnesses as highly recurrent, malignant disorders that occur far more frequently than previously thought. Interdisciplinary knowledge transfer could help to increase our understanding of the pathophysiology of these disorders as well as provide grounds for better recognition and treatment of patients with manic and/or depressive symptoms.