Lancet review focuses on bipolar II disorder

A recent Lancet review has focussed on the much understudied bipolar II disorder and the related bipolar spectrum disorders.Bipolar II disorder is defined by recurrent periods of highs and lows of mood, thinking and activity. These periods can vary in severity, duration and frequency, and can occur in combinations of manic or hypomanic and depressive symptoms in the same episode. Bipolar II disorder is less well understood than Bipolar I disorder; however, recent advances have related to Bipolar II and related disorders. In his Lancet seminar article, Franco Benazzi has provided a review of Bipolar II disorder.Kraepelin first described manic-depressive insanity in 1913. Benazzi notes that "Kraepelin's no-priority approach to the basic symptoms of mood disorders is the opposite of the approach of the current most commonly used diagnostic system, the diagnostic and statistical manual of mental disorders, fourth edition, text revision (DSM-IV-TR)."In DSM-IV-TR, mood disorders are divided into bipolar disorders and depressive disorders with hypomania being the basic feature that distinguishes the two groups. Hypomania is present in bipolar disorder but is absent in depressive disorders. The symptoms of mania and hypomania are similar in DSM-IV-TR except that mania is defined by an increased severity of symptoms and presence of psychosis. Benazzi's review goes on to discuss the many differences between mania, which defines bipolar I disorder, and hypomania, which defines bipolar II disorder.Benazzi notes that "the blurring of the boundaries between bipolar disorders and depressive disorders is mainly based on changes in the definition of bipolar II disorder, and on the re-emergence of the concept of mixed depression."The review notes the basic, distinguishing features of bipolar II disorder compared with major depressive disorder are lower age of onset, more recurrences, more bipolar (type I and II) family history, more atypical depressions, and more mixed depression.Mixed depression is defined by the combination of depression and non-euphoric, usually sub-syndromal, manic or hypomanic symptoms. It is present in both bipolar I and II disorders as well as the major depressive disorders. Benazzi notes that "compared with non-mixed depression, it is more common in bipolar disorders, lower age at onset, longer duration, worse outcome, and poorer response to treatments," and states that a categorical definition for mixed depression is questionable, noting that "mixed depression has a moderate diagnostic stability, which does not support a categorical distinction." He goes on to point out the clinical implications associated with mixed depression asserting that "depression should be systematically assessed for concurrent manic or hypomanic symptoms, which, if present, should lead to a careful probing for history of mania or hypomania."On the topic of treatment options, Benazzi emphasised that antidepressants are not efficacious in acute mania and hypomania, and can actually induce, rather than prevent such episodes.In summary, Benazzi notes the need for more controlled pharmacological studies that take into consideration the mixed profiles that commonly characterise bipolar disorders.Reference...