A major depressive disorder (MDD) is a severe depression, one that satisfies the criterias for an advanced depressive condition. It the most severe cases, it gets the features of a depressive psychosis, including symptoms such as hallucination of voices and delusions.
How is depression diagnosed?
A depressive disorder is diagnosed in the clinical interview, that is by the the doctor or psychotherapist asking the patient questions. The diagnose is supported by observations how the patient appear in the clinical situation. A self-questionnaire can be helpful.
In many cases the depression doesn't satisfy the criterias for a major depression. If a more low-grade depression goes on for a long time, it is called dysthymia. Dysthymia is sometimes callad non-major chronic depression or minor depression.
The difference between major depression and dystfmia is one of intensity. It is more or less the same disease, with the same kind of feelings and symptoms. The treatments also are of the same kind. Dysthymia is of a less intense kind and going on for a long time, two years or more.
The third kind of depression is the depression in the bipolar disease. This is different since it includes a component of mania, which is the opposite of depression.
Symptoms of the major depressive disorder (MDD)
- Feelings of sadness;
- Markedly diminished interest or pleasure in almost all activities;
- Significant loss or gain of weight without dieting, or markedly increase or decrease of appetite;
- Disturbance of sleep, either as insomnia (unable to fall asleep) or hypersomnia (sleep to much);
- Enhancement (agitation) or inhibition of thoughts or body movements;
- Feelings of weakness or lack of energy;
- Feelings of worthlessness or of guilt, without reason;
- Diminished ability to think, concentrate or take decisions;
- Recurrent thoughts of death, especially suicide, a suicide attempt or a plan to commit suicide
(These are criterias for major depressive disorder, MDD, from the psychiatric diagnostic manual DSM-IV.)
At least one of the first two groups of symptoms (sadness or diminished interest or pleasure) must be present, together with at least four of the other symptoms during the last two weeks. If so, the patient can be diagnosed as having a major depressive disorder (MDD).
The symptoms must not, though, be explained by substances such as alcohol, drugs or medications. They must neither be a part of a somatic medical condition, nor of any other psychiatric condition such as grief, a bipolar disorder or a schizo-affective syndrome.
Are lab exams valuable?
Lab exams are not relevant in the diagnosing of depression. However, the first time the diagnose is settled, it is useful to exam the levels of thyroidhormones and of calcium, to exclude a the most common hormonal causes of depression.
Also a general lab screening is often done, to make sure that there is no somatic disease going on that might contribute to the depression, interfere with the symptoms or inhibit the degradation of the antidepressant drugs.
X-ray for depression?
X-ray examinations, including CT and MR scan of the brain don't add any valuable information.
EEG (electroencephalography) for depression?
EEG is a method for recording electrochemical activity in the brain. It is used f.eks. in cases of suspected epileptic seizures. EEG is not relevant in diagnosing depression.
When the diagnose is settled - how is depression treated?
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