[The bipolar spectrum: research and clinical perspectives]

Abstract

Although epidemiologic figures place the lifetime prevalence of bipolar disorders at about 1%, current evidence indicates that the spectrum of bipolar disorders may account for 3-6% of the general population. This summarizes two decades of research conducted by the author and other investigators that supports the existence of such a spectrum that at the one extreme merges with severe psychotic disorder and at the other with temperamental dysregulation. The enlargement of the territory of bipolar disorders is due to new data that have validated mixed, rapid cycling, and "soft" bipolar conditions. The hallmark of bipolar I disorders is mania; extreme psychotic pictures often emerge when mania is mixed with depression, giving rise to "dysphoric mania". Attenuated or soft bipolar conditions refer to major depressive episodes interspersed with milder hypomanic excursions; the latter may occur spontaneously or upon pharmacologic challenge with antidepressants. Bipolar II disorder is often characterized by cyclothymic intermorbid or premorbid temperament. Bipolar III refers to major depressives without hypomanic episodes, yet arising from the background of a relatively stable level of hyperthymic temperamental adjustment and/or bipolar family history. These soft bipolar conditions are particularly liable to depressive rapid cycling as well as to depressive mixed states. The proper diagnostic characterization of these patients is important because new anticonvulsant treatments (as well as practical educational approaches to address these patients' temperament-based rythmopathy) need to be applied in their clinical care.