Bipolar Spectrum Disorder / 대한정신약물학회지

ABSTRACT

The concept of bipolar disorder is an ongoing process, still in evolution, although its roots can be found from ancient Greek. Until recently, it was believed that no more than 1% of the general population has bipolar disorder. But literature on the lifetime prevalence of the bipolar spectrum disorder suggests rates of 4-5%. Bipolar spectrum disorder is a longitudinal diagnosis characterized by abnormal mood swings comprising some of the following cross-sectional clinical states mania, hypomania, mixed states, hyperthymic temperament, major depressive episode, and depressive mixed state. Failure to recognize subthreshold expressions of mania, such as hypomania, cyclothymia, and hyperthymia, contributes to the frequent under-diagnosis of bipolar disorder. There are several reasons for the lower rate of recognition of subthreshold manic symptoms, when compared to the analogous pure depressive one. These include the lack of subjective suffering, enhanced productivity, egosyntonicity, diurnal and seasonal rhythmicity associated with many of the manic and hypomanic symptoms, and the psychiatrists' difficulty in differentiating with personality disorders. In addition, most patients with bipolar spectrum disorder seek treatment for depression, rather than mania or hypomania. Therefore clinicians often miss the diagnosis of bipolar spectrum disorder. The recent 10 years of researches have suggested that 30-55% of patients with major depressive disorder are actually identified with broader spectrum of bipolar disorders. However, 48% of patients of bipolar disorder consulted 3 or more professionals before receiving a correct diagnosis, and 10% consulted 7 or more for their first diagnosis of bipolar disorder. Several studies have documented that patients often wait as long as 10 years for the correct diagnosis of bipolar spectrum disorder. This delay in diagnosis often has substantial adverse results. Patients do not get the appropriate treatment to alleviate their symptoms. They may even get treatments that exacerbate their symptoms, such as prescription of antidepressants precipitating mania and producing rapid cycling. The concepts of hypomania, cyclothymia, mixed state, depressive mixed states, hyperthymic temperament are the new areas of studying mood disorders in recent 20 years. The authors will review the studies on various subtypes of bipolar spectrum disorder with their historic aspects, and introduce the suggested screening tests for bipolar spectrum disorder in clinical practice.