That Wikipedia article doesn't adequately explain what this is. "Atypical Depression" isn't a diagnosis unto itself. The DSM-IV criteria in that article are actually the criteria for the "With Atypical Features" specifier. This is a specifier which clarifies or extends the criteria for an underlying Depressive Disorder (ex. Major Depressive Disorder, Dysthymic Disorder). That is, the criteria listed for Atypical Depression must be
in addition to the criteria for a Depressive Disorder.
The "With Atypical Features" specifier mainly stands in contrast to the "With Melancholic Features" specifier. It should not be used if the patient meets the criteria for "With Melancholic Features":
Quote:
A. Either of the following, occurring during the most severe period of the current episode:
- loss of pleasure in all, or almost all, activities
- lack of reactivity to usually pleasurable stimuli (does not feel much better, even temporarily, when something good happens)
B. Three (or more) of the following:
- distinct quality of depressed mood (i.e., the depressed mood is experienced as distinctly different from the kind of feeling experienced after the death of a loved one)
- depression regularly worse in the morning
- early morning awakening (at least 2 hours before usual time of awakening)
- marked psychomotor retardation or agitation
- significant anorexia or weight loss
- excessive or inappropriate guilt
For reference, these are the criteria for a Major Depressive
Episode:
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A. Five (or more) of the following symptoms have been present during the same 2-week period and represent a change from previous functioning; at least one of the symptoms is either (1) depressed mood or (2) loss of interest or pleasure.
Note: Do not include symptoms that are clearly due to a general medical condition, or mood-incongruent delusions or hallucinations.
- depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g., feels sad or empty) or observation made by others (e.g., appears tearful). Note: In children and adolescents, can be irritable mood.
- markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly every day (as indicated by either subjective account or observation made by others)
- significant weight loss when not dieting or weight gain (e.g., a change of more than 5% of body weight in a month), or decrease or increase in appetite nearly every day. Note: In children, consider failure to make expected weight gains.
- insomnia or hypersomnia nearly every day
- psychomotor agitation or retardation nearly every day (observable by others, not merely subjective feelings of restlessness or being slowed down)
- fatigue or loss of energy nearly every day
- feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly every day (not merely self-reproach or guilt about being sick)
- diminished ability to think or concentrate, or indecisiveness, nearly every day (either by subjective account or as observed by others)
- recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or a specific plan for committing suicide
B. The symptoms do not meet criteria for a Mixed Episode (See linked section).
C. The symptoms cause clinically significant distress or impairment in social,
occupational, or other important areas of functioning.
D. The symptoms are not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition (e.g., hypothyroidism).
E. The symptoms are not better accounted for by Bereavement, i.e., after the loss of a loved one, the symptoms persist for longer than 2 months or are characterized by marked functional impairment, morbid preoccupation with worthlessness, suicidal ideation, psychotic symptoms, or psychomotor retardation.
A Major Depressive Disorder, then, is the presence of one or more Major Depressive Episodes. It may be classified as either single-episode (296.2X) or recurrent (296.3X). A Major Depressive Disorder should have one of these mandatory specifiers: Mild, Moderate, Severe Without Psychotic Features, Severe With Psychotic Features. Additionally, it may have several optional specifiers: Chronic, With Catatonic Features, With Melancholic Features, With Atypical Features, With Postpartum Onset. Catatonic, Melancholic, and Atypical are mutually exclusive. The Chronic specifier requires that the full criteria for a Major Depressive Episode be met
continuously for at least 2 years. It can also have the In Partial Remission or In Full Remission specifier depending on the age of the last Major Depressive Episode.
Dysthymic Disorder is essentially a less severe, but chronic version of a Major Depressive Episode. The criteria for Dysthymic Disorder (300.4) are:
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A. Depressed mood for most of the day, for more days than not, as indicated either by subjective account or observation by others, for at least 2 years. Note: In children and adolescents, mood can be irritable and duration must be at least 1 year.
B. Presence, while depressed, of two (or more) of the following:
- poor appetite or overeating
- insomnia or hypersomnia
- low energy or fatigue
- low self-esteem
- poor concentration or difficulty making decisions
- feelings of hopelessness
C. During the 2-year period (1 year for children or adolescents) of the disturbance, the person has never been without the symptoms in Criteria A and B for more than 2 months at a time.
D. No Major Depressive Episode (See linked section) has been present during the first 2 years of the disturbance (1 year for children and adolescents); i.e., the disturbance is not better accounted for by chronic Major Depressive Disorder, or Major Depressive Disorder, In Partial Remission.
Note: There may have been a previous Major Depressive Episode provided there was a full remission (no significant signs or symptoms for 2 months) before development of the Dysthymic Disorder. In addition, after the initial 2 years (1 year in children or adolescents) of Dysthymic Disorder, there may be superimposed episodes of Major Depressive Disorder, in which case both diagnoses may be given when the criteria are met for a Major Depressive Episode.
E. There has never been a Manic Episode (See linked section), a Mixed Episode (See linked section), or a Hypomanic Episode (See linked section), and criteria have never been met for Cyclothymic Disorder.
F. The disturbance does not occur exclusively during the course of a chronic Psychotic Disorder, such as Schizophrenia or Delusional Disorder.
G. The symptoms are not due to the direct physiological effects of a substance e.g., a drug of abuse, a medication) or a general medical condition (e.g., hypothyroidism).
H. The symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.
Dysthemic Disorder should be classified as either Early Onset (age <21) or Late Onset (age >= 21). As with a Major Depressive Disorder, it may receive the With Atypical Features specifier, however it does not permit the Catatonic, Melancholic, or Postpartum specifiers. It also doesn't permit the Chronic specifier, merely because Dysthymic Disorder is inherently chronic.
In any case, it's important to realize that the DSM-IV criteria are only a portion of the full DSM-IV description for each disorder. This leaves out a lot of important information included in the Diagnostic Features, Associated Features and Disorders, Specific Age and Gender Features, Prevalence, Course, Familial Pattern, and (perhaps most importantly) the Differential Diagnosis sections.
Even if you do have the full DSM-IV available, I have to give the usual caveats about the dangers of self-diagnosis. As well, the DSM-IV is an important resource and set of guidelines, but it's not the sum entirety of mental health or the practice of psychiatry.