Diagnosis

There are no laboratory tests to assist in the diagnostic process, so instead we look for clusters of clinical symptoms that we associate together as a syndrome. The various affective syndromes are made up of symptoms involving mood, thought, perception, biological functioning and behaviour and are classified using systems of classification such as DSM-IV (Diagnostic and Statistical Manual IV) and ICD-10 (International Classification of Disease 10). Both provide specific diagnostic criteria for each disorder and these handout are based on the latter as it is the one used most widely by doctors in the UK.

For clinical purposes we suggest a systematic description of the disorder based on ICD-10:

  1. The Episode
    1. Type
    2. Special Features
    3. Severity
  2. The Course
  3. Preceding Stressors
  4. Other Diagnostic Categories

The Episode

Type:

 

Manic Episode

Depressive Episode

Mood

elation
irritability

mood low most of the time
anhedonia
anxiety (common)

Speech & Thought

over talkative
pressure of speech
flight of ideas
full of plans(usually unfulfilled)
grandiose ideas
may develop delusions (mood congruent)

slow speech
poverty of thought
pessimistic, hopeless
suicidal ideas and/or intent
may develop delusions (mood congruent)

Biological functions

diminished sleep
reduced or increased appetite
increased libido

disturbed sleep (often early morning wakening)
anergia
decreased appetite/weight loss
reduced libido

Perception

may develop hallucinations if severe

may develop hallucinations if severe

Behaviour

overactive
unrealistic plans
impulsive
overspending
aggressive
disinhibited (inc. sexually)

avoids social interaction
self neglect
may show psychomotor retardation or agitation
actions in preparation for suicide

Minimum duration

1 week

2 weeks

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Special Features:

Psychotic symptoms - Hallucinations and delusions can occur in severe depression and mania. Delusions are usually mood congruent e.g. delusions of grandeur in mania. Delusions of poverty or guilt in depression. Hallucinations are usually auditory and in the second person.

"Neurotic" Symptoms - Most commonly anxiety symptoms but prominent obsessive compulsive or hypochondriacal symptoms may occur, particularly in the elderly.

Melancholia -This refers to a severe depression where biological symptoms are prominent i.e. weight loss or marked anorexia, early morning wakening, diurnal variation (with mood worse in the morning), psychomotor retardation or agitation.

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Severity:

The severity of a depressive episode depends upon the number of individual key symptoms, which are present, the intensity of these symptoms and the effect upon the person’s level of functioning.

 

 

Symptoms

Duration

Mild

At least 2 typical symptoms (depressed mood, anhedonia, fatiguability) and at least 2 other symptoms (biological symptoms and/or suicidal ideation).
No symptoms are present to an intense degree.

At least 2 weeks

Moderate

At least 2 typical symptoms (see above) plus at least 3 (and preferably 4) other symptoms.
Several symptoms are liable to be present to a marked degree but this is not essential if a particularly wide range of symptoms are present.

At least 2 weeks

Severe

All 3 typical symptoms plus at least 4 other symptoms, some of which should be of severe intensity, should be present.
Note that marked agitation or retardation may make the patient unable to describe their symptoms fully.
Mood congruent delusions and/or hallucinations may be present.

Usually 2 weeks but if particularly severe may be made sooner.

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The Course

There are four common patterns :

Single episode

Recurrent depressive disorder (a.k.a. unipolar affective disorder) - there should have been at least 2 episodes reaching the criteria for mild, moderate or severe depression, lasting at least 2 weeks and they should have been separated by several months without significant mood disturbance.

Bipolar affective disorder (a.k.a. manic depression) - there should have been at least 2 episodes reaching the criteria for a mood disorder, one of which must have been mania/hypomania, lasting at least 2 weeks and they should have been separated by several months without significant mood disturbance.

Chronic depression - meets the criteria for mild, moderate or severe depression, lasting at least 2 years.

In addition there is the less common:

Mixed affective episode - lasts for at least 2 weeks and is characterised by either a mixture or a rapid alteration (usually within a few hours) of hypomanic/manic, and depressive symptoms.

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Preceding Stressors

Affective disorders are frequently preceded by stressful life events or experiences of varying severity.

Other diagnostic categories:

Dysthymia is a form of mild depression which has a chronic course and does not meet the criteria for a recurrent depressive disorder (DSM-IV requires that the symptoms should be present for at least two years).

Cyclothymia is a milder form of bipolar disorder with persistent instability of mood, involving numerous periods of mild depression and elation. It may be a personality variant.

Schizoaffective disorder. This diagnosis should be limited to cases where diagnostic criteria for both schizophrenia and a mood disorder occur during the same episode. Otherwise the diagnosis is of the predominant syndrome.

 

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