edition of the manual. Using somewhat different  criteria, however, it has been estimated
that short-duration hypomania occurs in 2.8%  of the population (compared with hypoma-
nia or mania in 5.5% of the population). Short-duration hypomani a may be more common
in females, who may present with more  features of atypical depression. 
Risk and Prognostic Factors
Genetic and physiological. A family history of mania is two to three times more common in
individuals with short-duration hypomania co mpared with the general population, but less
than half as common as in individuals with  a history of syndromal mania or hypomania.
Suicide Risk
Individuals with short-duration hypomania ha ve higher rates of suicide attempts than
healthy individuals, although not as high as the rates in individuals with syndromal bipo-
lar disorder.
Functional Consequences of Short-Duration Hypomania
Functional impairments associated specifically  with short-duration hypomania are as yet
not fully determined. However, research suggests that individuals with this disorder have
less work impairment than individuals with  syndromal bipolar disorder but more comor-
bid substance use disorders, particularly alco hol use disorder, than individuals with major
depressive disorder. 
Differential Diagnosis
Bipolar II disorder. Bipolar II disorder is characterized by a period of at least 4 days of
hypomanic symptoms, whereas short-duration hypomania is characterized by periods of