Cyclothymia

From the Greek ‘alternating mood’, the term Cyclothymia was first used in psychiatry by E. Hecker in 1877 and was used by Emil Kraepelin as a synonym for the newly defined category of Manic-Depressive Insanity. Kraepelin described as subjects with a cyclothymic temperament ”…people who constantly oscillate hither and tither between the two opposite poles of mood, sometimes ’rejoicing to the skies, sometimes sad as death.”

Diagnostic Criteria
Cyclothymic Disorder (DSM IV, US)
• For at least 2 years the presence of numerous periods with hypomanic symptoms and numerous periods with depressive symptoms not meeting the criteria for a Major Depressive Episode.
Note: In children and adolescents the duration must be at least 1 year.
• During the above 2-year period (1 year in children and adolescents), the person has not been without the symptoms in Criterion A for more than 2 months at a time.
• No Major Depressive Episode, Manic Episode or Mixed Episode has been present during the first 2 years of the disturbance.
Note: After the initial 2 years (1 year in children and adolescents) of Cyclothymic Disorder, there may be superimposed Manic or Mixed Episodes, in which case both Bipolar I Disorder and Cyclothymic Disorder may be diagnosed, or Major Depressive Episodes, in which case both Bipolar II Disorder and Cyclothymic Disorder may be diagnosed.
• The symptoms in Criterion A are not better accounted for by Schizoaffective Disorder and are not superimposed on Schizophrenia, Schizophreniform Disorder, Delusional Disorder or Psychotic Disorder not otherwise specified.
 The symptoms are not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition (e.g., hyperthyroidism).
 The symptoms cause clinically significant distress or impairment in social, occupational or other important areas of functioning.

Cyclothymia (ICD 10)
A persistent instability of mood, involving numerous periods of mild depression and mild elation. This instability usually develops early in adult life and pursues a chronic course, although at times the mood may be normal and stable for months at a time. The mood swings are usually perceived by the individual as being unrelated to life events. The diagnosis is difficult to establish without a prolonged period of observation or an unusually good account of the individual's past behavior. Because the mood swings are relatively mild and the periods of mood elevation may be enjoyable. Cyclothymia frequently fails to come to medical attention. In some cases this may be because the mood change, although present, is less prominent than cyclical changes in activity, self-confidence, sociability or appetite behavior. If required, age of onset may be specified as early (in late teens or the twenties) or late.

Diagnostic Guidelines
The essential feature is a persistent instability of mood involving numerous periods of mild depression and mild elation, none of which have been sufficiently severe or prolonged to fulfil the criteria for Bipolar Affective Disorder or Recurrent Depressive Disorder. This implies that individual episodes of mood swings do not fulfil the criteria for any of the categories described under Manic Episode or Depressive Episode.
Includes:
 affective personality disorder
 cycloid personality
 cyclothymic personality

Differential Diagnosis
This disorder is common in relatives of patients with Bipolar Affective Disorder and some individuals with Cyclothymia eventually develop bipolar affective disorder themselves. It may persist throughout adult life, cease temporarily or permanently, or develop into more severe mood swings meeting the criteria for bipolar affective disorder or recurrent depressive disorder.