Catatonic disorders Health Article

Causes

CATATONIC SCHIZOPHRENIA.The cause of schizophrenia remains unknown. During the past decade, however, research has pointed to abnormalities in structure or function of certain areas of the brain, including the limbic system, the frontal cortex, and the basal ganglia. These three regions are interconnected, so that dysfunction in one area may be related to structural problems in another. Brain imaging of living people and studies of the brains of deceased persons point to the limbic system as the potential site of pathology in at least some, if not most, schizophrenic patients.

DEPRESSION WITH CATATONIC FEATURES.Mood disorders are believed to be at least partially caused by irregularities in production of neurotransmitterswithin the brain. Neurotransmitters are chemicals that conduct impulses along a nerve from one nerve cell to another. Two of the most important neurotransmitters associated with depression are norepinephrine and serotonin. In animal studies, virtually all effective antidepressant medications affect the receptors for these neurotransmitters. Dopamine is another neurotransmitter that plays a role in the development of depressive disorders.

CATATONIC DISORDER DUE TO A GENERAL MEDICAL CONDITION.Numerous medical conditions can cause psychiatric symptoms. Some of the more common are infectious, metabolic, and neurological conditions. Catatonic symptoms have been linked to earlier infection with encephalitis and to Parkinson's disease. Although the appearance of patients with post-encephalitis catatonia may be similar to that of catatonic schizophrenic patients, the majority of post-encephalitic patients are not psychotic. Oliver Sacks vividly describes catatonic disorder due to encephalitis and Parkinson's disease in his 1973 book Awakenings.

Symptoms

CATATONIC SCHIZOPHRENIA.Catatonic schizophrenia is a form of thought disorder with prominent motor symptoms and abnormalities. These symptoms include:

• Catalepsy, or motionlessness maintained over a long period of time.
• Catatonic excitement, marked by agitation and seemingly pointless movement.
• Catatonic stupor, with markedly slowed motor activity, often to the point of immobility and seeming unawareness of the environment.
• Catatonic rigidity, in which the person assumes a rigid position and holds it against all efforts to move him or her.
• Catatonic posturing, in which the person assumes a bizarre or inappropriate posture and maintains it over a long period of time.
• Waxy flexibility, in which the limb or other body part of a catatonic person can be moved into another position that is then maintained. The body part feels to an observer as if it were made of wax.
• Akinesia, or absence of physical movement.

DEPRESSION WITH CATATONIC FEATURES.Within the category of mood disorders, catatonic symptoms are most commonly associated with bipolar I disorder. Bipolar I disorder is a mood disorder involving periods of mania interspersed with depressive episodes. Symptoms of catatonic excitement, such as random activity unrelated to the environment or repetition of words, phrases and movements may occur during manic phases. Catatonic immobility may appear during the most severe phase of the depressive cycle. The actual catatonic symptoms are indistinguishable from those seen in catatonic schizophrenia. It is also possible for catatonic symptoms to occur in conjunction with other mood disorders, including bipolar II disorder (in which a milder form of mania called hypomania occurs); mixed disorders (in which mania and depression occur at the same time); and major depressive disorders.

CATATONIC DISORDER DUE TO A GENERAL MEDICAL CONDITION.Symptoms of catatonic disorder caused by medical conditions are indistinguishable from those that occur in schizophrenia and mood disorders. Unlike persons with schizophrenia, however, those with catatonic symptoms due to a medical condition demonstrate greater insight and awareness into their illness and symptoms. They have periods of clear thinking, and their affect (emotional response) is generally appropriate to the circumstances. Neither of these conditions is true of patients with schizophrenia or severe depression.

Demographics

According to the handbook used by mental health professionals to diagnose mental disorders, the Diagnostic and Statistical Manual of Mental Disorders,fourth edition, Text Revision, also known as the DSM-IV-TR, between 5% and 9% of all psychiatric inpatients show some catatonic symptoms. Of these, 25%–50% are associated with mood disorders, 10%–15% are associated with schizophrenia, and the remainder are associated with other mental disorders. Catatonic symptoms can also occur in a wide variety of general medical conditions, including infectious, metabolic and neurological disorders. They may also appear as side effects of various medications, including several drugs of abuse.