136 Bipolar and Related Disorders
A hypomanic episode should not be confused wi th the several days of euthymia and re-
stored energy or activity that may follow remiss ion of a major depressive  episode. Despite the
substantial differences in duration and severi ty between a manic and hypomanic episode, bi-
polar II disorder is not a “milder form” of bipo lar I disorder. Compared with individuals with
bipolar I disorder, individuals with bipolar II di sorder have greater chronicity of illness and
spend, on average, more time in the depressive phase of their illness, which can be severe and/
or disabling. Depressive symptoms co-occurr ing with a hypomanic episode or hypomanic
symptoms co-occurring with a depressive episod e are common in individuals with bipolar II
disorder and are overrepresented in females, pa rticularly hypomania with mixed features. In-
dividuals experiencing hypomania with mixed fe atures may not label their symptoms as hy-
pomania, but instead experience them as depr ession with increased energy or irritability.
Associated Features Supporting Diagnosis
A common feature of bipolar II disorder is impulsivity, which can contribute to suicide at-
tempts and substance use disorders. Impulsivit y may also stem from a concurrent person-
ality disorder, substance use disorder, anxiet y disorder, another mental disorder, or a
medical condition. There may be heightened levels of creativity in some individuals with
a bipolar disorder. However, that relationship  may be nonlinear; th at is, greater lifetime
creative accomplishments have been associated  with milder forms of  bipolar disorder, and
higher creativity has been f ound in unaffected family members. The individual’s attach-
ment to heightened creativity during hypomanic episodes may contribute to ambivalence