The psychiatrists answering questions can provide information about diagnosis and treatment, but cannot address how this information may apply to an individual situation. The term cyclothymia was first used in 1877 and has been employed in three ways. One use of the term is simply as a synonym for bipolar disorder. A second use of the term is to describe a kind of temperament in which people have frequent mood shifts within a normal range. A third use refers to sub-threshold mood disorders in which people experience mild highs and lows.
Cyclothymia appears to be genetically related to bipolar disorder.
At least two major studies found increased rates of cyclothymia in the relatives of people with bipolar disorder, but no increase above the population rate in relatives of people with major depression. These observations raise the question of whether mood stabilizing medications such as lithium might be useful for people with cyclothymia. There has been some suggestion that this is the case, though the issue has not been systematically studied. Whether stress makes cyclothymia worse is not certain as careful studies of this relationship have not been carried out. In general, though, people with an unstable mood probably benefit from creating stability in the structure of their life.