Cyclothymia

Cyclothymia, also called cyclothymic disorder, is a type of chronic mood disorder widely considered to be a milder or subthreshold form of bipolar disorder. Cyclothymia is characterized by numerous extreme mood disturbances, with periods of hypomanic symptoms alternating with periods of mild or moderate depression.
An individual with cyclothymia may feel stable at their baseline level but experience noticeable shifts to an emotional high during hypomanic episodes with symptoms similar to those of mania but less severe, and emotional lows involving depressive symptoms that do not meet the criteria for a major depressive episode. To meet the diagnostic criteria for cyclothymia a person must experience this alternating pattern of emotional highs and lows for a period of at least two years with no more than two consecutive symptom free months. For children and adolescents the duration must be at least one year.^[1]
While diagnosis of cyclothymia is becoming more common, it is not as frequent as that of bipolar disorder. Diagnosis of cyclothymia presupposes absence of a major depressive episode, manic episode or mixed episode, which would qualify the individual for diagnosis of another mood disorder. When such episodes manifest after an initial diagnosis of cyclothymia, the individual may qualify for a diagnosis of bipolar I or bipolar II disorder. Although estimates vary greatly, 15–50% of cases of cyclothymia later fit the diagnostic criteria for bipolar I and/or bipolar II disorder (resulting in a diagnosis of bipolar I or II with cyclothymic features).^[2]
Although the emotional highs and lows of cyclothymia are less extreme than those of bipolar disorder, the symptomatology, longitudinal course, family history and treatment response of cyclothymia are consistent with bipolar spectrum.^[3] Lifetime prevalence of cyclothymic disorder is 0.4–1%. Frequency appears similar in men and women, though women more often seek treatment. Unlike with bipolar I disorder, people with cyclothymia are more likely to be either somewhat or fully productive,^{[citation needed]} and sometimes even hyper-productive.
Cyclothymia is similar to bipolar II disorder in that it presents itself in signature hypomanic episodes. Because hypomania is often associated with exceptionally creative, outgoing, and high-functioning behavior, both conditions are often undiagnosed. As with most of the disorders in the bipolar spectrum, it is the depressive phase that leads most sufferers to get help.