Why So Many Classifications of Bipolar Disorder?

Question: Why So Many Classifications of Bipolar Disorder?

Answer: When evaluating symptoms and giving names to bipolar disorder - also called manic depression - and bipolar disorder's many subsets, there are no absolutes.

In their book We Heard the Angels of Madness, authors Diane and Lisa Berger describe bipolar disorder as "a virulent disorder with many faces" and liken it to the multi-headed Hydra of Greek mythology. Just as the Hydra sprouted several new heads for each one slain, researchers and clinicians find that for each new fact learned about bipolar disorder, more questions are raised. Symptoms are different from one person to the next. The severity of symptoms also differs. Facets of personalities combine to create additional faces on the monster.

Thus, researchers, clinicians, and practitioners face a wide array of challenges in order to "codify" each diagnosis. In response, classification systems, subsets and specifiers have been developed in an attempt to standardize the diagnostic process.

In the United States, the primary system is the one found in The Diagnostic and Statistical Manual of Mental Disorders also known as the DSM-IV. This classification system organizes the mood disorders under the heading of Clinical Disorders (Axis I).

DSM-IV Listing - Mood Disorders

• Depressive Disorders
  • Dysthymic Disorder
  • Major Depressive Disorder

• Bipolar Disorders
  • Bipolar Disorder I
  • Bipolar Disorder II
  • Cyclothymic Disorder

• Mood Disorder Due to a General Medical Condition
• Substance-Induced Mood Disorder

To each of the above disorders, any of a number of specifiers (e.g., "with seasonal pattern," "with catatonic features," "first episode manic," etc.) can be added to clarify the severity or course of the disorder for an individual patient.

The International system is the ICD-10, The International Statistical Classification of Diseases and Related Health Problems, tenth revision. The ICD-10 provides a structure of "families" or related disorders and breaks them down initially into many more categories than does the DSM-IV. Bipolar disorder is within the family of mood (affective) disorders.

ICD-10 Listing - Mood Disorders

• Manic Episode
  • Hypomania
  • Mania without psychotic symptoms
  • Mania with psychotic symptoms
  • Other manic episodes
  • Manic episode, unspecified

• Bipolar Affective Disorder
  • Current episode hypomanic
  • Current episode manic without psychotic symptoms
  • Current episode manic with psychotic symptoms
  • Current episode mild or moderate depression
  • Current episode severe depression without psychotic symptoms
  • Current episode severe depression with psychotic symptoms
  • Current episode mixed
  • Currently in remission
  • Other bipolar affective disorders
  • Bipolar affective disorder, unspecified

• Depressive Episode
  • Mild depressive episode
  • Moderate depressive episode
  • Severe depressive episode without psychotic symptoms
  • Severe depressive episode with psychotic symptoms
  • Other depressive episodes
  • Depressive episode, unspecified

• Recurrent Depressive Disorder
  • Current episode mild
  • Current episode moderate
  • Current episode severe without psychotic symptoms
  • Current episode severe with psychotic symptoms
  • Currently in remission
  • Other recurrent depressive disorders
  • Unspecified

• Persistent Mood [Affective] Disorders
  • Cyclothymia
  • Dysthymia
  • Other persistent mood [affective] disorders
  • Unspecified

• Other Mood [Affective] Disorders

• Unspecified Mood [Affective] Disorder

In addition to the two formally recognized diagnostic classifications outlined above, there are quite a few other descriptive systems to be found in the literature. Many of these have been developed by researchers for specific projects or presented as possible alternatives as more is learned about these disorders. One such classification system is that of Young and Klerman who distinguish between six subtypes of manic depression.

Young and Klerman Subtypes

• Bipolar I - Mania and Major Depression
• Bipolar II - Hypomania and Major Depression
• Bipolar III - Cyclothymia
• Bipolar IV - Antidepressant Induced Hypo/mania
• Bipolar V - Major Depression with a family history of Bipolar Disorder
• Bipolar VI - Unipolar Mania

by Kimberly Read

References:
American Psychiatric Association (2000). Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Text Revision (DSM-IV-TR^TM).

Berger, D., & Berger, L. (1991). We Heard the Angels of Madness. New York, NY: William Morrow and Company, Inc.

Bipolar Connection. (2002). Classification of Bipolar Disorder.

World Health Organization. International Statistical Classification of Diseases and Related Health Problems (10th Revision).