The Mood Disorders section includes disorders that have a disturbance in mood as the predominant feature. The section is divided into three parts. The first part describes mood episodes (Major Depressive Episode, Manic Episode, Mixed Episode, and Hypomanic Episode) that have been included separately at the beginning of this section for convenience in diagnosing the various Mood Disorders. These episodes do not have their own diagnostic codes and cannot be diagnosed as separate entities; however, they serve as the building blocks for the disorder diagnoses. The second part describes the Mood Disorders (e.g., Major Depressive Disorder, Dysthymic Disorder, Bipolar I Disorder). The criteria sets for most of the Mood Disorders require the presence or absence of the mood episodes described in the first part of the section. The third part includes the specifiers that describe either the most recent mood episode or the course of recurrent episodes.
The Mood Disorders are divided into the Depressive Disorders ("unipolar depression"), the Bipolar Disorders, and two disorders based on etiology—Mood Disorder Due to a General Medical Condition and Substance-Induced Mood Disorder. The Depressive Disorders (i.e., Major Depressive Disorder, Dysthymic Disorder, and Depressive Disorder Not Otherwise Specified) are distinguished from the Bipolar Disorders by the fact that there is no history of ever having had a Manic, Mixed, or Hypomanic Episode. The Bipolar Disorders (i.e., Bipolar I Disorder, Bipolar II Disorder, Cyclothymic Disorder, and Bipolar Disorder Not Otherwise Specified) involve the presence (or history) of Manic Episodes, Mixed Episodes, or Hypomanic Episodes, usually accompanied by the presence (or history) of Major Depressive Episodes.
Major Depressive Disorder is characterized by one or more Major Depressive Episodes (i.e., at least 2 weeks of depressed mood or loss of interest accompanied by at least four additional symptoms of depression).
Dysthymic Disorder is characterized by at least 2 years of depressed mood for more days than not, accompanied by additional depressive symptoms that do not meet criteria for a Major Depressive Episode.
Depressive Disorder Not Otherwise Specified is included for coding disorders with depressive features that do not meet criteria for Major Depressive Disorder, Dysthymic Disorder, Adjustment Disorder With Depressed Mood, or Adjustment Disorder With Mixed Anxiety and Depressed Mood (or depressive symptoms about which there is inadequate or contradictory information).
Bipolar I Disorder is characterized by one or more Manic or Mixed Episodes, usually accompanied by Major Depressive Episodes.
Bipolar II Disorder is characterized by one or more Major Depressive Episodes accompanied by at least one Hypomanic Episode.
Cyclothymic Disorder is characterized by at least 2 years of numerous periods of hypomanic symptoms that do not meet criteria for a Manic Episode and numerous periods of depressive symptoms that do not meet criteria for a Major Depressive Episode.
Bipolar Disorder Not Otherwise Specified is included for coding disorders with bipolar features that do not meet criteria for any of the specific Bipolar Disorders defined in this section (or bipolar symptoms about which there is inadequate or contradictory information).
Mood Disorder Due to a General Medical Condition is characterized by a prominent and persistent disturbance in mood that is judged to be a direct physiological consequence of a general medical condition.
Substance-Induced Mood Disorder is characterized by a prominent and persistent disturbance in mood that is judged to be a direct physiological consequence of a drug of abuse, a medication, another somatic treatment for depression, or toxin exposure.
Mood Disorder Not Otherwise Specified is included for coding disorders with mood symptoms that do not meet the criteria for any specific Mood Disorder and in which it is difficult to choose between Depressive Disorder Not Otherwise Specified and Bipolar Disorder Not Otherwise Specified (e.g., acute agitation).
The specifiers described in the third part of the section are provided to increase diagnostic specificity, create more homogeneous subgroups, assist in treatment selection, and improve the prediction of prognosis. Some of the specifiers describe the clinical status of the current (or most recent) mood episode (i.e., Severity/Psychotic/Remission Specifiers), whereas others describe features of the current episode (or most recent episode if the episode is currently in partial or full remission) (i.e., Chronic, With Catatonic Features, With Melancholic Features, With Atypical Features, With Postpartum Onset). Other specifiers describe the course of recurrent mood episodes (i.e., Longitudinal Course Specifiers, With Seasonal Pattern, With Rapid Cycling). The specifiers that indicate severity, remission, and psychotic features can be coded in the fifth digit of the diagnostic code for most of the Mood Disorders. The other specifiers cannot be coded.
