ECNP consensus meeting. Bipolar depression. Nice, March 2007

Diagnosis and epidemiology: DSM-IV, specifically its text revision DSM-IV-TR, remains the preferred diagnostic system. When employed in general population samples, prevalence estimates of bipolar disorder are relatively consistent across studies in Europe and USA. In community studies, first onset of bipolar mood disorder is usually in the mid-teenage years and twenties, and the occurrence of a major depressive episode or hypomania is usually its first manifestation. Since reliable criteria for delineating unipolar (UP) and bipolar (BP) depression cross-sectionally are currently lacking, there is a longitudinal risk - probably over 10% - that initial UP patients ultimately turn out as BP in the longer run. Its early onset implies a severe potential burden of disease in terms of impaired social and neuropsychological development,most of which is attributable to depression.