Bipolar disorder

What is bipolar disorder?Bipolar disorders are characterised by recurrent episodes of elevated mood and depression, which are accompanied by changes in activity or energy and associated with characteristic cognitive, physical, and behavioural symptoms (fig 1⇓). The term mania is used when elevated mood is severe and sustained or associated with psychotic symptoms, leading to marked disturbance of behaviour and function. Hypomania refers to less severe elevations in mood, which may be fairly brief, with a lower level of disturbance that usually does not bring the person to medical attention; however, hypomania may progress to mania. Bipolar disorders are divided into bipolar I disorder with episodes of mania and bipolar II disorder in which only episodes of hypomania occur (fig 1). Although traditionally viewed as opposite poles, manic and depressive symptoms often co-occur, giving rise to “mixed” states.2View larger version: In this window In a new window Fig 1 Diagnostic criteria for bipolar disorder. DSM-IV=Diagnostic and Statistical Manual of Mental Disorders, fourth edition; ICD-10=international classification of diseases, 10th revisionIn community samples, as many people experience milder episodic highs (subthreshold) as those who meet the criteria for bipolar disorder,3 and together they form the bipolar spectrum. Cyclothymia refers to a subset of milder disorders with repeated short cycles of hypomania and mildly lowered mood occurring regularly over two or more years. There is controversy about whether these milder disorders, which can overlap with personality characteristics, should be included under the diagnosis of bipolar disorder,4 and where to set the threshold between unipolar and bipolar disorder for those with episodes of depression and mild symptoms of hypomania.5