Major Depressive Disorder

Diagnostic Criteria
The essential feature of Major Depressive Disorder is a clinical course that is characterized by one or more major depressive episodes without a history of panic, mixed, or hypomanic episodes.

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) deressed 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.

(1) 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.

(2) 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).

(3) 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.

(4) insomnia or hypersomnia nearly every day

(5) psychomotor agitation or retardation nearly every day (observable by others, not merely subjective feelings of restlessness or being slowed down)

(6) fatigue or loss of energy nearly every day

(7) feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly every day (not merely self-reproach or guilt about being sick)

(8) diminished ability to think or concentrate, or indecisiveness, nearly every day (either by subjective account or as observed by others)

(9) recurrent thoughts of feath (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 noot meet criteria for a Mixed Episode (see p. 365).

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.

Prevalence
According to the DSM-IV-TR, the lifetime risk for Major Depressive Disorder (MDD) in community samples has varied fro 10% to 25% for women and from 5% to 12% for men. The point prevalence of MDD in adults in community samples has varied from 5% to 9% for women and from 2% to 3% for men. Ethnicity, education, income, or marital status does not appear to be related to prevalence rates of MDD.

Major Depressive Disorder (MDD) may begin at any age. The average age at onset is in the mid-20s. Epidemiological studies indicate that the age at onset is decreasing for those born more recently. The course of MDD, recurrent, is variable. Some people have isolaed episodes that are separated by many years without any symptoms of depression, however, some people have clusers of episodes, and some have increasingly frequent episodes as they grow older. Some evidence suggests that the periods of remission generally last longer early in the course of he disorder. At least 60% of people with MDD, single episode, can be expected to have a second episode. There is a 70% chance of having a third episodes after a second episode. People who have had three episodes have an even higher chance of having a fourth episode (90%). Approximately 5%-10% of people with MDD, single episode, may develop a manic episode, for example, Bipolar I Disorder).

Follow-up studies suggested that one year after the diagnosis of MD, 40% of individuals still have symptoms that are severe enough to meet criteria for a full major depressive episode, approximately 20% of these individuals continue to have some symptoms that no longer meet full criteria for a major depressive episode, and 40% have no mood disorder. The severity of the first major depressive episode may predict recurrence of MDD. In addition, general medical conditions appear to be a risk factor for recurrent episodes. Chronic general medica conditions and substance dependence (especially alcohol or cocaine dependence) may contribute to the onset or exacerbation of MDD.

Articles
Prevalence of depression by race.pdf‎

Media Links
[http://www.youtube.com/watch?v=IeZCmqePLzM What is depression? #1]

Major Depressive D/O