Mental health articles

Bipolar disorders are so-called because, during their course, a patient may experience mood states at either extreme of the mood spectrum. The defining feature of these disorders is abnormal elevation of mood, which is out of proportion to normal happiness. This elation may be accompanied by excessive optimism, impatience, irritability and impaired functioning when it is termed hypomania, or by excitation, excessive activity and often grandiose delusions, that constitute mania.

Distinct episodes of depression may also occur, either sequentially or separated by variable periods of normal mood. Bipolar affective disorder is a life-long, relapsing and remitting illness, with a strong genetic component (almost 70% concordance between monozygotic twins) that affects men and women equally. Its onset is typically in late adolescence or early adult life, and its overall prevalence is about 2% in the population. Clinical subtypes are recognised, with Type I (classical manic-depressive) disorder being slightly less common than Type II (depressive-hypomanic) disorder (Box 9.1). The latter appears to have a younger onset and to be more likely to affect women. Women with bipolar affective disorder have a high risk of suffering puerperal psychosis in the fi rst three to four weeks following childbirth. An episode of mania follows up to 50% of deliveries to sufferers, compared to one in 500 for women without the disorder.

Clinical subtypes of bipolar mood disorders

Mania: episode of elated and excited mood often with psychotic features

Hypomania: excessive cheerfulness and energy without psychosis

Bipolar I disorder: recurrent episodes of mania with much less frequent depressive phases

Bipolar II disorder: recurrent episodes of depression with less frequent hypomanic phases

Bipolar III disorder: manic episodes triggered by antidepressant treatment of an apparently unipolar depression (also termed switching)

Rapid cycling bipolar disorder: four or more severe mood episodes occurring in a single year

Mixed affective state: simultaneous occurrence of features of mania and depression

Schizoaffective disorder: clear mood (often mania) and schizophrenic features present simultaneously

Cyclothymia: periodic alternation of mild elation and mild depression (cf. dysthymia)

Tags: bipolar mood disorders, disorders, symptoms