Seasonal affective disorder is another name for a type of mood disorder whose mood episodes correspond to the seasons or characteristic times of the year.

Seasonal pattern specifiers in the DSMEdit

Seasonal pattern specifiers are used to describe (or specify) the course of of some mood disorders whose mood episodes correspond to the seasons or characteristic times of the year.

The DSM uses seasonal pattern specifiers to describe the following mood disorders:

In order for a mood disorder to be considered to have a seasonal pattern the following must be true:

  • There is a regular relationship between the beginning of a major depressive episode and the time of year (for example, depression regularly starting in the fall or winter)
  • Full remissions also occur at a specific time of year (for example, depression disappears in the spring)
  • In the last 2 years or more major depressive episodes have always and only occurred during a specific season
  • Seasonal major depressive episodes have substantially outnumbered nonseasonal major depressive episodes throughout the person's lifetime

While this description does not specify the presence of manic, mixed, or hypomanic episodes, these types of episodes often also occur at other times of the year (for example, manic episodes during the summer).

Mood disorders as diagnosed by the DSM edit
Mood episodes: Major depressive episode Manic episode Mixed episode Hypomanic episode

Depressive disorders: Major depressive disorder Dysthymic disorder Depressive disorder NOS (PMDD)

Bipolar disorders: Bipolar I disorder Bipolar II disorder Cyclothymic disorder Bipolar disorder NOS

Other mood disorders: Mood disorder due to a general medical condition Substance-induced mood disorder Mood disorder NOS

Episode specifiers: Severity Psychotic Remission Chronic Catatonic Melancholic Atypical Postpartum

Course specifiers: Longitudinal Seasonal (SAD) Rapid cycling