What defines cyclothymic disorder in contrast to bipolar disorders?

• A. Not meeting criteria for major depressive, manic, or hypomanic episodes for at least 2 years (1 year in children), with symptoms present most of the time but symptom-free for no more than 2 months.
• B. At least one major depressive episode and one manic episode.
• C. Chronic anxiety with intermittent mood shifts.
• D. Numerous periods of hypomanic symptoms and depressive symptoms that meet full criteria for mood episodes.

Answer: (D)

Cyclothymic disorder involves chronic, fluctuating mood with many periods of hypomanic symptoms and depressive symptoms that never reach full criteria for a manic, hypomanic, or major depressive episode. This pattern must persist for at least two years in adults (one year in children/adolescents), with symptoms present most of the time and only brief, occasional symptom-free gaps (no more than about two months).

This contrasts with bipolar disorders, where mood changes consist of discrete episodes that meet full DSM criteria for either mania/hypomania and major depressive episodes. In bipolar I, there are manic episodes; in bipolar II, there are hypomanic episodes plus major depressive episodes. So cyclothymia is about subthreshold, chronically fluctuating mood symptoms rather than full-blown mood episodes.