Mood Disorders: Depression
The depressive disorders are characterized by lifelong vulnerability to episodes of disease, involving depressed mood or loss of interest and pleasure in activities. Individuals may demonstrate ongoing po-tential for cycling of mood from euthymia to depression to recovery and sometimes to hypomania or mania. When individuals cycle to hypomania or mania, then a diagnosis of bipolar II (in the case of hypomania) or bipolar I (in the case of mania) is made. When the mood disorder is severe, assessment for psychosis is essential.
In most definitions of depression, a distinction is drawn be-tween a feeling state of dejection, sadness, or unhappiness, which may be brief in duration, and a clinical syndrome characterized by persistent sadness, profound discouragement, or despair which persists two weeks or more and is associated with a change from previous functioning. This clinical syndrome invariably involves alterations in mood experienced by an individual as a feeling of sadness, irritability, dejection, despair, or loss of interest or pleas-ure. Associated neurovegetative or biological signs of depression include impairment in sleep, appetite, energy level, libido and psychomotor activity. Cognitive manifestations of the depressive syndrome include distortions about oneself, one’s experience in the world and the future, accompanied by self-blame and indeci-sion. These core symptoms of depression are evident in children or adolescents with MDD although the depressed mood may be manifested by irritability or social withdrawal. Older adults may show a preponderance of somatic preoccupation and memory impairment in association with the signs of MDD. The current DSM-IV-TR criteria (A) for MDD are noted below.
The use of the term melancholia to refer to the depres-sive syndrome became less common as depression and manic– depressive disease were used more frequently in the early 20th century. Currently, the specifier with melancholic features is ap-plied to the diagnosis of MDD if it is associated with a profound loss of interest and lack of reactivity to favorable external events. Other symptoms characteristic of melancholia include a distinct quality to the depressive mood characterized by marked wors-ening in the morning, early morning awakening, psychomotor retardation or agitation, significant anorexia and excessive guilt. These melancholic features are noted as a modifier of MDD in III-R, and in DSM-IV (American Psychiatric Association, 1994).
Our current definitions of MDD emphasize suicidal ideation, thoughts of death and suicide attempts as a cardinal criterion symptom of the disorder. Suicidality is the feature of depres-sive disorder that poses substantial risk of mortality in the dis-ease. Prevention of suicide, more than any other treatment goal, requires immediate intervention and may require hospitalization. The risk for subsequent completed suicide for an individual hos-pitalized for an episode of severe MDD is estimated to be 15%.